Here's a resource I've used before to try and help ID some
Canadian Chevy/GMC engines. The screenshot below is showing the engine block casting# 5843350 as found in 10 different 1953 Canadian built vehicles or stand alone engines.
Dates codes of those blocks with that casting number (where available) are listed from Dec 1952 through Feb 1953, all falling into the 1953 model year range.
Look for the engine block "date" casting codes mentioned by klhansen above and we can confirm when the block was cast.
