Resuggestion, thanks to Cashew for the info!

Sale 1:

https://backpack.tf/profiles/76561198185982134#!/compare/1586908800/1586995200

https://backpack.tf/profiles/76561198124799470#!/compare/1587081600/1587254400

untrace

sale 2:

https://backpack.tf/profiles/76561198124799470#!/compare/1591142400/1591315200

https://backpack.tf/profiles/76561198141949945#!/compare/1591228800/1591315200

Sold for 6 keys

sale 3:

https://backpack.tf/profiles/76561198141949945#!/compare/1591315200/1591401600

https://backpack.tf/profiles/76561198250846294#!/compare/1575849600/1591574400

Untrace

sale 4:

https://backpack.tf/profiles/76561198250846294#!/compare/1591574400/1591747200

https://backpack.tf/profiles/76561197993725164#!/compare/1591488000/1591574400

Untrace

sale 5:

https://backpack.tf/profiles/76561197993725164#!/compare/1591660800/1591747200

https://backpack.tf/profiles/76561198066686957#!/compare/1591574400/1591660800

Bulk

sale 6:

https://backpack.tf/profiles/76561198066686957#!/compare/1591660800/1591747200

https://backpack.tf/profiles/76561198280693486#!/compare/1591574400/1591660800

Untrace

sale 7:

https://backpack.tf/item/7457980414

https://backpack.tf/profiles/76561198297023624#!/compare/1589155200/1589328000

not unusual till this compare.

sale 8:

https://backpack.tf/profiles/76561198297023624#!/compare/1589500800/1590105600

https://backpack.tf/profiles/76561198340634356#!/compare/1589500800/1589846400

QS

sale 9:

https://backpack.tf/profiles/76561198340634356#!/compare/1590537600/1590624000

https://backpack.tf/profiles/76561198850178158#!/compare/1590537600/1590624000

untrace

sale 10:

https://backpack.tf/profiles/76561198850178158#!/compare/1591056000/1591142400

https://backpack.tf/profiles/76561198046461179#!/compare/1587081600/1591142400

Can trace 2 keys

sale 11:

https://backpack.tf/profiles/76561198005032783#!/compare/1584662400/1584748800

https://backpack.tf/profiles/76561198314789145#!/compare/1582934400/1586217600

Untrace

sale 12:

https://backpack.tf/profiles/76561198447992809#!/compare/1586649600/1586736000

https://backpack.tf/profiles/76561198142375270#!/compare/1587081600/1588464000

untrace

sale 13:

https://backpack.tf/profiles/76561198142375270#!/compare/1588809600/1589241600

https://backpack.tf/profiles/76561198841279602#!/compare/1589155200/1589241600

QS

sale 14:

https://backpack.tf/profiles/76561198350816720#!/compare/1587254400/1587427200

https://backpack.tf/profiles/76561198337734785#!/compare/1587340800/1587427200

QS

sale 15:

https://backpack.tf/profiles/76561198337734785#!/compare/1588118400/1588204800

https://backpack.tf/profiles/76561198112779962#!/compare/1588118400/1588636800

Keys(?)

Sale 16:

$13.85 / $1.78 = 7.78 keys

$13.61 / $1.79 = 7.60 keys <--- https://backpack.tf/item/6906724151

$13.61 / $1.79 = 7.60 keys

$13.61 / $1.81 = 7.52 keys

$13.61 / $1.85 = 7.36 keys

$14.5 / $1.99 = 7.29 keys <--- https://backpack.tf/item/6470447265

Bot.tf:

https://bot.tf/stats/item?def=30919&q=5&ef=Showstopper&craft=1&aus=0&ks=0

1 @ 6 keys

1 @ 5.5 keys,

3 @ ~4.5 keys

Total sales @:

4.5, 4.5, 4.5, 5.5, 6, 6, 7.5, 7.5, 7.5, 7.5, 7.5, 8 keys

Buyers up to ~4.5 keys,

sellers at ~5 keys,

https://bot.tf/stats/listings/Y5ZLO7X2 <--- unsold for ~1 week, https://backpack.tf/item/6463080659

https://backpack.tf/item/7036723567 <--- recently listed, dropped from ~6 keys over a month....

https://bot.tf/stats/listings/4O9XLRKG <--- unsold for ~1 week,

Cashew's Part:

newer sales on marketplace/bot.tf combined with the 3 sellers below 5.3 indicate 7.5 is too high to include

New Sales:

https://backpack.tf/profiles/76561198282751347#!/compare/1592265600/1594080000

https://backpack.tf/profiles/76561199005154104#!/compare/1593907200/1594080000

https://backpack.tf/profiles/76561198841279602#!/compare/1593993600/1594080000

Untrace / QS

https://backpack.tf/profiles/76561198280693486#!/compare/1592611200/1592697600

https://backpack.tf/profiles/76561198358296372#!/compare/1592611200/1592697600

Untrace

https://backpack.tf/profiles/76561198074371786#!/compare/1591228800/1594252800

https://backpack.tf/profiles/76561198850274253#!/compare/1594166400/1594252800

Bulk / QS

https://backpack.tf/profiles/76561198850274253#!/compare/1594684800/1594771200

https://backpack.tf/profiles/76561198358296372#!/compare/1594684800/1594857600

QS / untrace

https://marketplace.tf/items/tf2/30919;5;u3001

$15.99 / $1.99 = 8.04 keys

$9.76 / $1.98 = 4.93 keys

$10 / $2.00 = 5.00 keys

15.83 / 1.98 = 7.99 keys

https://bot.tf/stats/item?def=30919&q=5&ef=Showstopper&craft=1&aus=0&ks=0 5 sales here since 6/21 below 5 keys, not entirely sure about including 6 here.

looks like we're down to 1 seller at 5.26, wouldn't be against a higher high end like 5.5 since there's a decent amount of sales for higher.

Taking 5 - 5.5 keys