Glenn Lyford

Does anyone have something similar and can tell me the toothcount,
DP, and arrangement of the gears from the dog clutch to the quick
change gearbox?

My feed plate indicates a 144T and two 36T gears are used, but my
understanding is that any combination that gives me a 1:4, 1:1, and 4:1
ratio (such as 24/96T, etc) and can fit on the banjo will work. If
this is so, then it would be a lot easier for me to reconstruct the feed
on this since I could use any other lathe gears of the right pitch that
I could find. Anyone see any problems with that approach?

You may need the larger gear to bridge to the QC box.
From about 1892 Hendey made an early form of QC, the Hendey-Norton. Norton
held the 1892 patent for it. I don't have the number, off hand.
Your machine looks even earlier, though.
Also, does anyone know off the top of their heads if the usual suspects
for lathe parts in the NE have anything for Hendeys? Plaza, Mermac, etc.?

A couple of years ago there was a guy posting here from Torrington, where they
were based. He had some Hendey machinery for display there, iirc. Perhaps you
could scout out that city to see if anything like that is still there.
Frank Morrison