Not a recognisable Myford accessory or even general lathe accessory to me. Could possibly be some kind of worm and wheel reduction gearbox?
A peek inside one or two of those inspection covers might help.
If you spin that disc coupling with the two pins sticking out of it, does the other shaft sticking out the side turn a tiny amount?
If it's a worm and wheel reduction box, could be someone was thinking of making a dividing head etc out of it.
Edited By Hopper on 03/07/2022 07:29:26