What you have is a BRNO 22F. A small ring Mauser.They are mostly found with square bridges with integral 19mm dovetails for which there are several rings available. Yours is a standard Mauser 98 pattern with a beautifully checkered front bridge. It also appears to be in very good condition to excellent condition. Since it is not possible to mount a scope without drilling and tapping the bridges or the left receiver wall I would strongly suggest that you do not alter this valuable rifle.
You can probably pick up a beat up .303 SMLE to take care of nuisance animals. You can also consider selling the rifle to a collector , buying a suitable used scoped rifle and pocket the difference.