Ok well the g&g PM4 light isn't the best option here is a better (much much better) choice. The PM4 light is a crappy clearsoft halfbreed and I can guess where you found it from. OVERPRICED.
King Arms M4A1
Full metal (except for the handguard, grip and stock of course) amazing quality, reliable internals and sells for around the 250-300 mark.
as for where you can find this amazing airsoft gun?
Sadly look at my name, see that little bar with "Age Verified"? It confirms to the community that I am 18+ years of age. Until you have that little banner underneath your name we cannot tell you where to find them.
To get age verified please read these three.
There you go you have all the tools to get started. Have good one mate.