'psteinmayers' suggestion is a good one, if your Gunsmith advises against firing your Krag.

Used cut-down Krag barrels, with a front sight attached, are often listed on ebay and sometimes sell for reasonable cost.

If you can find a competent Gunsmith, who can switch Krag barrels at reasonable cost, this may be a viable route to go.

Plug the stock holes and you can have a shootable and more attractive heirloom from your Wife's family. (The trick is to not put much money into such an endeavor, because such an altered Krag is not worth very much - maybe $200-250). But, the fun is great!

p.s. Welcome to the KCA Forum and congratulations on your recent marriage!