A couple.

Sale 1: Sold for 44 keys

https://backpack.tf/profiles/76561198869506063#!/compare/1584230400/1584316800

https://backpack.tf/profiles/76561198382115458#!/compare/1584144000/1584316800

Sale 2: Sold for keys, but histories do not match.

https://backpack.tf/profiles/76561197994587943#!/compare/1580688000/1588118400

https://backpack.tf/profiles/76561198216374215#!/compare/1586131200/1588204800

Sale 3: Sold for 38 keys + 22.33 refined

https://backpack.tf/profiles/76561198062756330#!/compare/1590105600/1590364800

https://backpack.tf/profiles/76561198267189538#!/compare/1590278400/1590364800

Rounds to 38 keys

Sale 4 & 5: Marketplace

https://marketplace.tf/items/tf2/644;5;u30

48.35 on March 28, 2020 (48.35/1.69 = 28.6 rounding to 29 keys)

81.99 on March 30, 2020 (81.99/1.69 = 48.514 rounding to 49 keys)

Classifieds:

https://gyazo.com/00f7d1e6e866aed343177f3d98a9a762

Sales at 29, 38, 44, and 49. Buyers at 38+. Excluding 29 and 38. Taking a range of 44-49 keys here.