I have a set. I ended up using a generic trim ring off of Ebay that is actually pretty convincing and fits well. I have another set of the 15x7's on order. They were supposed to be available at the end of December, but no word yet. I ordered them from Coker since they actually own Wheel Vintiques so I figured that would be my best shot at actually getting them. I am assuming they will fill their own orders before everyone elses. I know 15x8 will work on the rear, as I had a set on my car. I think 15x8 will be a problem on the front of a 65 as you can't run a really wide tire up there as they rub on the back of the fender when turning. 235's will rub for sure and anything much narrower on a 8 inch rim will probably be too narrow for the rim. These are the trim rings I used.
https://www.ebay.com/itm/365938539159