With our new trailer I had to buy new rims since we went with a larger diameter tire. Purchased them from Discount Tire for $100 each in addition to getting new tires and metal valve stems. Sold the stock wheels and tires for an amount equal to the price of the new rims. I was amazed with how many calls I got for the stock rims/ tires off a Craigslist Ad.
You just need a zero off-set and, important, make sure the hub cap/ center cap will clear your hubs. We bought some Visions and their cap was too short; I had to go MacGyver and make them work.