https://www.millertire.com/products/wheels-by-type/front-tractor-imp-wheels/blank/15x-7-rim-blank/ Also, check with hamber "Phillips" I have purchased wheel shells from him.
Which centers are you wanting to use? You will need to know the diameter. For example, a 15" early Ford steelie center is about 12&5/8" and a 16" early Ford steelie center is about 13&5/8".
Have you measured the centers you want to use? Not all Chevy centers are the same. When you have that measurement you can begin shopping.
ordered some from Miller tire, then found some at Heywheel a little cheaper . So thanks to big deuce for leading to Miller