If you had to choose 1 type

[Nickle]

Winchester M1 Garand for me, and I've already got it.

2nd choice would be an 03-A3 or 1903.

If you're talking much newer stuff, an early Fed Ord M14A or a Romanian Dragunov.

And, yes, I have all of them now, and more.

 

[AntiqueWeapons.org]

I like Mausers because they're easier to find, can be bought with less money, are several variations & manufacturers & parts are everywhere.