I just got a flyer from chevs of the 40s and they are selling cut to fit custom door panels in about 50 varieties for about $150 a set. Some with door rests... Might be easier to buy the panel with the design you want and then cover it or paint w/vinyl paint of your color choice.

'51 Chevy 1/2 ton w/'62 261, HEI, offy, fentons, dual carter/webbers, t-5 & 12 bolt posi