When I purchased my '51 Chevy 1/2 ton, it came with a 235 already installed, but it is badly in need of a rebuild (I made the mistake of starting it on front of the garage with the door open, took quite a while for the smoke to clear out of there

) The casting number is 3835911, I believe it is out of a 53-55 Corvette? (some resources also call it "First Series"). I was wondering where some of you all purchased your rebuild kits? I see a few websites of companys that sell them, but I would like to use a place that someone has had good experience with in the past.
EDIT: casting code is G20 4, so I guess it was cast on July 20, 1954