This was my fix for the time being. I took apart an old rear axle and used the spring. I had to cut about 1/2” off due to the larger cup size on the rear. I assembled into the RZR and rode about 20 miles with no issue.
So the cheap-o internal round wire retaining rings seem to be made of unobtanium, unless you get lucky and call up a manufacturer that will offer to help out on an individual basis seems like.. I'm trying to find something mere humans can get their hands on, so I ordered a few of these from Fastenal, which are not round, but neither is the axle cup groove. Less than $10 for 4 landed, should be here next week. And Fastenal does COD which is nice these days
I am making an assumption that the ears will not interfere with any axle rotation as well, will be verifying. Worst case they can be grinded off if the other specs fit.