Ian, really sorry to hear about your truck. Just realized I met you briefly at the Allendale Show,- my blue ‘53 truck was parked beside yours! My advice is to begin searching for a 1954-1962 235 engine. The later the 235 engine the better, as improvements were made over the years. Also, parts and repairs are less expensive and available. I have heard good things about Performance Automotive/Machine Shop located in Greeneville. They may be able to help locate a 235 engine. I actually found mine in a JC scrap yard. Be prepared to spend some bucks for a proper rebuild, but it will bring you many miles and years of joy. I will send a pm if I find an engine for sale locally.
Don/RdsLessTaken