I recently purchased a “SCORPION EVO SWITCHBACK CHARGING HANDLE” from Manticore Arms (link below).
Be careful not to damage the little loop pin thingy (pretty sure that’s what it’s called). If you do, I think you can buy more of those from CZ directly, but don’t quote me on that.
I would also highly recommend the safety delete from HB industries if you are having the stock safety switch rubbing your finger.
Link to charging handle: https://manticorearms.com/scorpion-evo-switchback-charging-handle
Link to safety delete: https://hbindustries.net/store/shop/cz-scorpion-evo-3-safety-delete-v2/