In your other thread, you mentioned the ones at Bass Pro Shops.
I've played the ones at Cabela's and they us IR guns, so some type of interface for the IR guns must exist.
...but I don't have any info on it
You could ditch the original hardware, use a PC, & retrofit the gun with an Ulitmarc AimTrak IR gun.
Then run the PC versions of hunting games as well as those emulated in MAME and Demul.
Don't remember all the supported games off the top of my head, but I will post them later if I get a chance.
The tracking on IR guns isn't quite as accurate as a true light gun that works on a CRT monitor.
It especially drives me nuts on the hunting games, but if you are willing to use the onscreen crosshairs instead of relying soley the gun sites, it works.
(It ruins the fun for me)
My old emulator PC setup consists of a 32" TV and Act Labs S-video guns.
They aren't made anymore, but they pop up on ebay every once in a while.
You could move the guts from one into your rifle and use it with the 36" CRT if it has an S-vid input.