just go to big five, they have sales on mosins a lot. can get for 98 dollars $,
also you normally get sling, ammo pouches, cleaning kit, and gaping tool
if you decide on a mosin, look down the barrel for pitting, make sure numbers match, check out the bolt and make sure it dosnt stick
if you find one you like clean the cosmoline out, by either heating up gun or gun cleaning solvents (hopps ect)
after clean take for a shoot and see what its quirks are. if possible buy the front end adjustment tool to adjust sights if not zeroed (they rarely are)