Hey sgt.rock, and sgt's. friend's daughter.
An inspiring post ... it is
so good to hear when the youngster's show talent and interest in marksmanship diciplines.
BUT, would such a gun be an ok starting point for a Re-stock and Re-barrel??
And if rebarreled, what would you guys think would be a suitable caliber for him to get the rifle chambered in?
IMO, stick with 6.5/55, at least for the short term.
Reading your post, I get the impression that encouraging her enthusiasm in rapidly developing her shooting skills is priority #1 at present. An unlimited budget to achieve this end ... was not implied by OP. Thus the question.
He wondered if his Husky 6.5x55 (sportered military rifle)could do the trick (with reloading of course) out to 1000m (or even 800).
More ammo, so as to be spending max trigger time at the steep part of her learning curve, that may be an appropriate use of available resources?.
I've been clanging small steel out to 1000+ with Bubba'd M96 Swedes for many decades now. Nearabouts 1/2 moa is where they can be tuned to shoot (assuming good conditions), out to 500 or so ... then openening to around 1 moa at 1000 .... and this being consistent too, in my experience.
A tuned Swede, with one of Tradeex's excellent $100 M38 barrels screwed on, well bedded, decently scoped, Bold trigger at 2 1/2 lbs pull, properly handloaded ... is a formidable shooting machine. This level of performamce/consistency is plenty good enough to focus the emphasis on shooting ability and learning to the read conditions.