Doh! You're 100% correct, was looking at a pic that looked like it didn't have the protrusion on the back end ...and didn't bother to look it up through Concoa, which has a fantastic set of .pdfs.
If the Concoa is used, I'd probably still go with the Victor because of the O2 issue, but I'd make sure to look through the available pics. I did look at the Victor, and if it were me, I'd probably still get a new CGA320 chrome nut, if not the nipple as well, as the nut appears chewed-up. Wish I could see the gauges better, though. One thing to always make sure of is that the gauges are zeroed out. HP gauge looks good, and I *think* the LP is good (there's a short vacuum range at the lower end).