[Arran]

 It looks like the chassis in this Truetone had one of those weird textured paints they used back then on test equipment, I've also seen it on some 1920s radios, sort of like a fine crackle finish. I have no idea how one would duplicate it, I found a formula for making a crystalized frosted finish by mixing naptha into whatever constituted enamel paint in those days. The closest that I have seen to that crackle paint was modern wrinkle pain like VHT sells for painting valve covers, but it's wrinkled not cracked. A lot of brand Z chassis used a gold hammer tone paint, Strombergs used a dark brown crystalized frosted paint on theirs, with copper plate underneath. Sometimes you can restore a textured finish by cleaning it really good with something like TSP and then by painting over it, I did that with an A.K speaker a few years ago.
Regards
Arran