If the '91 Carbine is still all orig Military,,crest in tact (many were ground), no sight or scope mt holes, no alterations in other words,,and a nice bore,,the price is good IMO. Hard to find unmolested rifles anymore and the Carbines seem to bring a premium.
Speer(?) used to make a .314 for the Ar/Mauser but I don't think they do anymore. I used a lot of them in SMLE's w/ slightly over size bores to get accuracy.
There's 32-20 cast bullets in that .314dia that'd work nice over 10 to 12gr of RedDot if you're in to that sort of thing. Don't know what's offered in jacketed for the 32-20. I shoot a lot of light loads in centerfire calibers and find them a lot of fun on the range.
Most bullet casters will size rifle bullets to what you want so you may be able to get full weight (150-170gr) bullets in .314d. and run them at decent velocity.