Ill have to look at my Parker, but I dont think thats a broken swivel stop mount. I know on Reed vises the factory put a plug in them so you could have it on the right or the left. Parker may have put that boss there for the same reason. All that swivel stop does is keeps it from swiveling, its not intended to hold the vise together. Theres a big ass bolt in the center of the vise thru a steel bushing that actually keeps both parts together.
Ive seen broken vises, but not at that point on quality American vises, believe those parts are cast steel not cast iron, so they would bend before cracking.
Buzz,
Reeds are excellent vises, and pretty darn tough and repairable. Disassemble the vise, clean all the old crud out. Make sure that the handle turns easily and there are no cracks in the castings. If the jaws dont line up when closed, no biggie, do the old machinist/gunsmith trick and file them so they are level.
If you need the jaws to be parallel to +/- .0002 for their entire travel, get a milling machine vise like a Kurt or Parlec but if you need something that will hold parts for general gunsmithing a Reed is awesome.
PS... Reeds have an oil hole near the handle that oils the front bearing.
