They have a nifty site:Armalite
My choice is the M15A2 which gives a grouping of bullets one inch in diameter at 100 yards. It has the accuracy important to a sniper.
At 1000 pounds (new) they are reasonably priced.
If your concern is the annoying "gun regulations" realize that you can order the individual "pieces" ship them in different packages....and therefore, you never bought a "gun," only plastic and metal precision-tooled-pieces.
Don't worry about needing to place your order today, there are a lot more where these come from.