The '53 powerglide engine is a great engine, however it is something of an oddball. It was the first 235 engine with high pressure lubrication, and insert bearings, and hydraulic lifters. The cam is unique to that engine, (maybe also early '54?) it is a forged cam, has the smaller bearing journals like the earlier engines, but has the hydraulic lifter grind. The oil pump may also be different. As far as I know, all the parts are available except maybe the cam. That being said, there should be no problem in getting your cam reground or getting a new cam ground to spec from a blank.
The side cover should fit if it is for a 235, and I would think you could drill and tap the holes for the valve cover, but I never looked at doing that. Alternatively you could get a different head.
I think it is a cool and unique engine, and I would not hesitate to use it. I have run mine for almost 40 years and two rebuilds.
this link may be of interest to you:
1953 engine codes Kurt
