Adding another sale to the range here, thanks Xergoyf.

SALES

sold for 17 keys

https://backpack.tf/profiles/76561198928421771#!/compare/1593475200/1593561600

https://backpack.tf/profiles/76561198100597709#!/compare/1591142400/1593734400

https://imgur.com/a/jF8jP8Y - backed up by bot.tf

MARKETPLACE

https://marketplace.tf/items/tf2/30763;5;u3023

Sold for 26 on April 7 (26/1.69 = 15.38 rounding to 15 keys)

Sold for 26.95 on April 19 (26.95/1.79 = 15.06 rounding to 15 keys)

Sold for 44.99 on May 30 (44.99/1.94 = 23.19 rounding to 23 keys)

https://backpack.tf/item/4952872896

CLASSIFIEDS

https://gyazo.com/6949d1e09a321b4fe30634596321a513

Seller at 15.

https://bot.tf/stats/listings/4WXKJ3ZZ - blaze has been at 17 for ~1 month, was only at 15 for a few days

https://bot.tf/stats/listings/4R06EWDK - first 15 listing

https://bot.tf/stats/listings/MGL20PK3 - last 15 listing

SUMMARY

2 @ 15 keys

1 @ 17 keys

1 @ 23 keys

CONCLUSION

23 is high due to multiple sales at lower, as well as past sellers at 15.

Going to take 15-17 here.