Mosins are one of the best deals in a bolt action rifle going. The rifles are inexepensive, and usually rearsenalled to excellent condition. My M38 was rearsenalled, counterbored, (creating a new muzzle crown about 3/4 inch inside the muzzle, worn from steel cleaning rods), and an M44 stock. It will give me 3 inch groups at 100 yards with Wolf ammo. I love it. Do NOT buy one with lots of visible wear, those have NOT been rearsenalled, which is done at the factory in Russia.
You should be able to pick up the Mosins for under $100 for any of the common ones, the M38 or M44 carbine, (only differance is the M44 has the permanantly attched pigsticker), and the long 91/30. All will give reasonable accuracy, known in the circle as "minute of nazi". The M39, M28, or other Mosin derivatives from Finland, tend to be very accurate, but are also about 3 to 4 times as expensive.
Ammo is DIRT cheap, and since the 7.62x54R, the longest serving military round ever, is still in production, we can STILL get surplus ammo! A bunch of Czech 1980s LPS steel core just came in, the succesor to the Czech Silvertip. To put it in perspective on price, the 20 round box of surplus Silvertip ammo, (always the most expensive way to buy), runs $1.49 at J&G Sales!!
As mentioned, surplus ammo is corrosive, which really only means I run a couple of patches down the bore, and along the bolt face, with ammonia Windex, to help kill the corrosive "salts". No corrosion I can find yet!
For $100, you should be able to get an M44, mucho ammo, and one other item I find absolutely neccesary - a slip on recoil pad.
Picture an M-1 Carbine, chambered in 30-06. Thats a Mosin carbine...Uncle Ivan must have been one tough customer...