You might want to check out the Harbor Freight 2-1/2-inch cast iron, clamp-on three-axis bench vise.
https://www.harborfreight.com/2-1-2-...ise-97160.html
For $20, I figured I'd take the risk. It's pretty sturdy and allows me to rotate whatever I'm working on to almost any angle. I notice it's on clearance now and no longer available at my local HF.
One note of caution: OPEN THE BOX IN THE STORE and check the tolerances. The first one I bought was so poorly machined that the outer jaw just flopped around. I had to hold it in position to tighten it.
I took it back and traded it for a better one. Now it's become a really useful tool. Easy to mount and remove from the bench. Will clamp to a 1-1/2" thick bench top or you can drill holes and mount it permanently.
I find I'm using it all the time to hold guns securely and safely while I'm working on them.