As usual, just pricing the unpriced unusuals

Sale on marketplace.tf: https://marketplace.tf/items/tf2/1112;5;u3027

May 12 2020: Sale at $10 (median key price: $1.90, 10/1.9=5.26 keys

There is also an other sale on April 30 2020 but it's older than 3 months so it can't be used in the price range (median key price: $1.82, 10/1.82=5.49 keys)

https://backpack.tf/item/5351416745 Only history I found with recent sale, which shows the item bought from marketplace.tf going into the buyer's inventory

With the valid sale, 5.26 keys rounds up to 5.5 keys, taking 5.5 keys as the value for my suggestion, the outdated sale also rounds up to 5.5, but as I said, it can't be used to price