Month 1 https://gladiator.tf/sales?item=Non-Craftable%20Unusual%20Taunt:%20The%20Boston%20Breakdance%20Unusualifier&at=2022-10-28T20:24:09.709Z

1 @ 2 keys 11 ref

2 @ 2 keys 17 ref

1 @ 2 keys 18 ref

1 @ 2 keys 18.11 ref

1 @ 2 keys 18.88 ref

3 @ 2 keys 34 ref

2 @ 2 keys 35 ref

1 @ 2 keys 37 ref

4 @ 3 keys

1 @ 3 keys 10 ref

1 @ 3 keys 15 ref

Month 2 https://gladiator.tf/sales?item=Non-Craftable%20Unusual%20Taunt:%20The%20Boston%20Breakdance%20Unusualifier&at=2022-09-28T20:24:09.709Z

1 @ 2 keys 1 ref

1 @ 3 keys 19.88 ref

4 @ 3 keys 20 ref

Month 3 https://gladiator.tf/sales?item=Non-Craftable%20Unusual%20Taunt:%20The%20Boston%20Breakdance%20Unusualifier&at=2022-08-28T20:24:09.709Z

1 @ 2 keys 11.11 ref

1 @ 2 keys 12 ref

1 @ 2 keys 12.55 ref

1 @ 2 keys 28.22 ref

1 @ 3 keys 19 ref

https://steamcommunity.com/market/listings/440/Unusual%20Taunt%3A%20The%20Boston%20Breakdance%20Unusualifier

Buyers at ~2 keys, highest sales up to ~2.75 keys, lower sellers around this value or lower

https://gladiator.tf/time-machine?item=Non-Craftable%20Unusual%20Taunt:%20The%20Boston%20Breakdance%20Unusualifier&at=2022-10-28T20:26:39.833Z

Page of sellers down to ~2.55 keys or lower

Credits Blaze:

2.25 - 2.55 / 2.6 should be okay here from scm sales / the sale you've provided

2.25 - 2.55 keys as Blaze suggested.