A good scope for a Krag with one of these sidemounts would be a Rudolph P. Noske 2.5 or 4X.  5-6" of eye relief puts the scope forward of both the bolt handle and safety.  They're not easy to find though, and they have a 7/8" tube.  Here's a pic of how they were mounted back then.  The idea was to keep the scope's line of sight as close as possible to being the same as the irons.  Course that's not going to be the case when it's offset to the side as it would have to be on a Krag.  To me they are a better scope than either the Alaskan or Texan.  One thing I really like is that the objective lens can be adjusted for focus.  Even with my bad right eye, I was able to adjust it to a sharp focus, without my glasses.  Authors Bob Bell and Nick Stroeble had Noske going under during WWII, but I just spied an ad in a 1947 Field and Stream, he was still making them!

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