Depends on what your plans are for the truck.
If it is going to be an original restoration then you should rebuild it if needed.

If it will be a general play and work truck then swap for a newer 235 or 261, either a used or rebuild one.
However, if the original frees up and runs get all the use you can out of it before swapping.

Grigg

•1951 GMC 250 in the Project Journals
•1948 Chevrolet 6400 - Detroit Diesel 4-53T - Roadranger 10 speed overdrive - 4 wheel disc brakes
•1952 Chevrolet 3800 pickup
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"First, get a clear notion of what you desire to accomplish, and then in all probability you will succeed in doing it..." -Henry Maudslay-