Just cash and carry at Walmart. Mounted them myself with new tubes and had them balanced at a local tire shop.
You could get a local shop to do everything, including the Nexems. Lots of options - Vredesteins are great, but twice the price. Jegs and Summit catalogs sell 165/15 tires to use on the fronts of race cars. If you can't find tubes locally, eBay lists a lot for $10. Each. If money is no object, and new wheels are in order, go to Hendrix wire wheel and get a package.
Good luck, Bob