compression test results.
All 72 340's had a forged crank. The only difference between 71 and 72 340's was 72's had a smaller intake valve (1.88 vs 2.02) and the pistons were changed for lower compression. In 73 the cast cranks came out. Some early 73's still had the steel crank, though. Your compression numbers really don't seem all that bad. probably needs bearings.
don