OP, parts for US made Krags are reasonably available. Boyds makes an after market stock. Different sites in the US have parts for sale as well. As far as ammo goes most 30-40 US Springfield made Krags I have loaded for have .311 diameter bores. When push comes to shove, yes this it heresy I know but I have done it on many an occasion, 303Brit brass will fire form easily in the chamber. The neck will be short but it will work.
One thing which makes all of the difference. You can purchase a 90% or better Springfield Krag mod 1898 including bayo in similar condition for under C$2000. A few years ago maybe a bit less because our dollar was on par or above the US dollar. But they do hold their value in collectable condition.
Chop the stock and knock 75% off the price of a complete correct piece. Condition, missing bits and pieces, rust, poor bore, galled screw heads, sight changes, cracks in stocks, missing hand guards etc and no matter the condition of the metal otherwise the price drops off dramatically.
Back in the 60s Krag carbines were offered in hardware stores like Marshal Wells, Army/Navy, SIR and through International Firearms in excellent condition for $12. I can remember the first one I bought in 1963 at the Marshal Wells store here in my small town. $12 and the manager of the store threw in a couple of boxes of surplus 303Brit. Those were the 48 round boxes as well. It was a gorgeous little carbine and looked great just the way it was to me. I threw on a 10 cent web sling to get by with the first fall and then a neighbor told me it was the wrong sling and gave me a surplus leather 1918 leather sling he had kicking around. I kept that rifle for years and ended up giving it to a friend. I never did shoot anything other than 303 Brit through it because even back then 30-40 commercial hunting ammo was next to impossible to find locally.
Without seeing the rifle you describe and from your extremely brief description it could cost you more to put the rifle back to its original state than you could purchase one that is already in good condition.
I don't like shooting my Krag because it is way to nice and no matter how hard I try, taking it to the range will happen, my fault or some nimrod that just has to pick it up and handle it without permission. So I make up a Martini action in 30-40 Krag. I really like the cartridge. When loaded to military specs it is the kissing cousin of the 303Brit.
Your call on this. Getting parts locally is like finding hen's teeth. Bringing up the parts from the US isn't to bad if you can find a way to bundle them all together so you aren't paying individual shipping charges/import/export charges.
Whatever it will be a labor of love that getting your money back from will be next to impossible.