A buddy of mine bought a SXS 12 ga and cut down the barrels, I think too far, and mounted rifle sights on the gun.
He used the sights off of a Remington Nylon 66, but you can get a number of single and double leaf express sights.
Works well for deer and hogs with standard slugs and buck.
A SXS shot gun has a short regulation (where the two barrels intersect) a rifle has a longer one and the barrels are regulated to a specific load.
I am hopeing to find another SXS with ejectors and a beaver tail forend in a shop for a good price to change into a 25 or 26" barrel with rifle sights.
On the rifle note, Merkel makes a SXS 30-06, for about 7 to 10K