I am interested in purchasing the JG T3 SG-1 (G3) I am fairly new to airsoft, so forgive my ignorance, but how would I go on upgrading this gun? what parts would I be looking for? what parts are compatible essentially. If I could get some help, that'd be great, thanks! 
http://www.airsoftmegastore.com/1880-400-fps-t3-sg-1-sniper-airsoft-aeg-rifle-t3-k1-jg-098-g3-sg1.aspx
*EDIT, no price range, whatever is top of the line...
What I need upgraded...
-Accuracy
-Range
-Metal body (I hear G&G and Classic Army make them but I couldn't find any in-stock)
-Wiring (replacing JG wiring, I hear its pretty bad)
-Whatever else you guys think I need xD
http://www.airsoftmegastore.com/1880-400-fps-t3-sg-1-sniper-airsoft-aeg-rifle-t3-k1-jg-098-g3-sg1.aspx
*EDIT, no price range, whatever is top of the line...
What I need upgraded...
-Accuracy
-Range
-Metal body (I hear G&G and Classic Army make them but I couldn't find any in-stock)
-Wiring (replacing JG wiring, I hear its pretty bad)
-Whatever else you guys think I need xD