Yeah me and my mate used to use Barter, a little while after we stumbled on another trading site that has a decent system for tracking bundles. Not sure how the size of userbase compares but if you ever fancy taking another dive into trading I’d check out https://lestrades.com/

This doesn’t sound like the exact thing you’re looking for but the arcade mode has a similar concept and might be quite close, also has other conversion and difficulty options.

https://csplusplus.com/binary-game/