I model the early 1950s and really want some pickups from pre-war period - the only thing better than a new pickup is a weathered, worn, old pickup!
I always try Amazon, it is quick and once in a while one of their associate sellers has something interesting . . . they have a Solido mid '30s Ford pickup right now that looks nice . . .
I find quite a few jut at diecastdirect by searching for pickups. There are about ten pages or more to go through, all scales, but you quickly find the 1:43 pickups from before the war, etc., and more than a few are quite inexpensive, even if the Brooklins aren't. Also Mint models, 300toys, and Buffalo road are worth seraching.