If you can get a clearer pic of the bottom of the magplate and the internals (take the slide off) I might be able to tell you what brand the gun is as well.
If it is "UK spec", chances are it's not a Tokyo Marui and I'm saying this based on what I've seen of players in the UK use while I was in the UK. The players I played with (arguably a younger bunch so not much money) tended to favour KJ Works (Alright brand and gas system is TM compatible) and WE for some reason or other.
ಠ_ಠLess QQ more Pew Pew
READY TO >> RACE