771 was their standard 3/8" combination wrench.
Short handle was a 771S (S for "short")
The short handle models outsold the longer models by about three-to-one (maybe four-to-one) on the smaller sizes. (Don't ask me why.)
Longer stuff - 15/16", 1-1/8", etc. - guys would usually go with the longer unit.
It is not a tappet wrench. Tappet wrench part numbers were T1, T1A, T2, etc.
The longer-handled 700-series combination wrenches in the smaller sizes are fairly uncommon now, particularly in 1/2" and 9/16".
There were other manufacturers who made them with long handles like that: Herbrand was one. I believe Armstrong still makes SAE combination wrenches in a longer-length style as well. I would guess there are others as well.
