Depends on your budget.... If it's a wall hanger (eg. you want something to complete your collection of era kit and you don't need it to fire) then a cheaper one is probably good enough. However if you actually want to game it expect around $450-600 for something decent.
Jeff (baker_jeff) is probably the guy to talk to since he made a pretty pimpin No.4 Lee Enfield http://www.airsoftcanada.com/showthread.php?t=75742