ThatIS NOT a good buy for a used gun with only one barrel??
As far as the cantilever system. You can purchase a cantilever barrel (1) with it all ready part of the barrel or (2)you can have a smith drill and tap the receiver for a scope base or (3)use a saddle mount system that untilizes the triggerhousing pin and ejector screw holes to mount it. (1) choice being the best option in my option if you don't want it to be a dedicated deer gun only, if you do then option (2) is just as good if done correctly. Hope this helps? e-mail me if you have further questions?
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