Try Plastic Performance Products 69 Starnes Cove Rd Asheville NC 28806
This guy makes plastic wheels white and Chrome plated from 50's 5 1/2 wide chevy/ford wheels to 11 inch wide dirt track wheels (all are sets of 4 with backs drilled for metal axes)
Do not know what current cost is for his listing pages w/ photos. He also does outstanding roll bars that can be built serval different ways