Being the pack rat that I am (would you believe TWO extra storage buildings) I'm sure I have some old Mark 1V or other aftermarket condensers. They're small enough to fit in front of nearly any radiator and that can be a problem. Everything was R-12 when these were in use and their size and fin count isn't what's needed to get the most out of 134A. In the small volume of a pickup cab, especially if insulated, one might do OK. I'll look tomorrow and if ones there it's yours for the gas money it'll take you to come get it. Remember these old condensers didn't have O ring or flare fittings, the hose just fit on a barbed tube and was held with an a/c hose clamp.
