Check the bores, the firing pins, and extractors.
Some of the Mosins/variants I have seen had demilled pins and had missing/broken extractors.
Not to worry though.
Plenty of replacement bolt assemblies on Amazon.
Just be sure the bore is clean and still has rifling.
Did they come with kits? If not. Get one.
The go/no-go gauge for the firing pin at least.
Look on the forums here as there are a lot of Mosin fanboys, me included.
And if you want good surplus ammo in 7.62x54R, go to
www.aimsurplus.com while the ammo is still cheap.