Are you talking about the bolt knob? As in switching the bolt knob from left to right or vice-versa? A new knob for the bolt handle? A new bolt handle for the bolt?
Or a right/left hand breech?
Or a side lever breech?
If you’re talking about switching between left and right handed breech, you can do that on a Gen2 by flipping the cocking plate underneath the breech. If you’re talking Gen1, either you can’t or you can flip the cocking lug on the bolt. Not too sure about a Gen1.
If you’re talking about a right or left hand breech or a sidelever breech, no. No one is making one for sale. There’s a couple of prototypes and personal builds though, and AFAIK, those people aren’t selling. There is ONE right or left hand breech that might work, but it comes with a WAR rifle/carbine and WAR doesn’t sell it separately.