Updating 3-year old price.

https://backpack.tf/classifieds?item=Egghead%27s%20Overalls&quality=11&tradable=1&craftable=1&australium=-1&killstreak_tier=0

Buy Orders start at 5.52, ~5.5 keys.

Sell Orders start at 5.94, ~5.95 keys.

Bot.tf Sales:

https://ibb.co/qsnHFsJ

https://ibb.co/hBb0v8B

1 Sold for 4.79, ~4.8 keys.

1 Sold for 4.85 keys.

1 Sold for 4.76, ~4.75 keys.

1 Sold for 4.45 keys.

No Marketplace.tf sales in the last 30 days.

SCM Sales:

https://ibb.co/17NjCv9

1 Sold for $12.28/ 2.23 = 5.5 keys.

1 Sold for $13.36/ 2.25 = 5.93, ~5.95 keys.

1 Sold for $13.12/ 2.31 = 5.67, ~5.65 keys.

1 Sold for $12.82/ 2.33 = 5.5 keys.

1 Sold for $12.44/ 2.30 = 5.4 keys.

Excluding any other sales due to them either being too low for buy orders, or too high for sell orders. I will be also excluding the sale for 5.95 keys, as I personally believe it's an outlier sale compared to the other sales made in the last 30 days. Going with 5.5 - 5.65 keys.