The best buy in milsurps is probably the Yugo Mausers (either M48 or M24/47) chambered in 8mm Mauser. That being said, I wouldn't recommend either to a new shooter.
I enjoy collecting milsurps that are historic and fully operational. Mostly own USGI Springfields since I'm retired USAF, had family members in the Army and I like military history even when I was forced to study it for PME. I visited the US Ordnance Springfield Armory museum in MA a few months ago and had a good time speaking with the park rangers learning the history of US rifle development and John Garand's work when he was employed there.
My two favorite milsurp shooters currently:
- M1898 Springfield Krag-Jorgenson 30-40 based on the Norwegian design with the neat flip-out loading cartridge box which was very innovative over 100 years ago. It has the smoothest bolt action I've ever experienced.
- K31 Swiss Karabiner. This is little rifle is super accurate and I've nailed bull's eyes numerous times at 100 yds with the standard iron sites. The straight-pull bolt is just fun to use too.
The 7.5x55mm Swiss ammo is not the cheapest ammo but I do see GP11 surplus for sale quite often and it is high quality. https://en.wikipedia.org/wiki/K31
I'll probably use the K31 with soft point ammo next time I go deer hunting.