you can buy a round carrier for a lt500. It uses all the stock components. im thinking lonestar? I had one in my old leagers arm. If I was you id get a arm for a banshee carrier. Best thing I ever did for my 500... Then go on ebay and buy a banshee axle assembly on the cheap...
DO you have any pics of the swing arm? I'm trying to identify the swing arm on my 'Zilla and Lonestar seems to be the closest, but in searching on the interwebs, I did not find an exact match. It certainly is not the stock unit. Round carrier, eccentric adjustment with a single pinch bolt on each side of the carrier section. trying to figure out what I need to get as far as replacement bearings and such. I will try to figure out how to get pictures of it using my phone and add them if able.
Thanks!