'King carp' - I don't believe the scope side-mount holes weaken the Krag receiver.

Looking at  the holes on your receiver, I believe they are spaced for the Weaver side-mount, that attaches to their 'Number 2' block. The block uses a pretty common gun-screw thread.

The Weaver-mount and Block are still made and show up on ebay, from time to time.
On a 'Sporter' this scope mount can be handy. but, it positions the scope slightly off-set and interferes with rotating the issue safety-lever.

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