I stand corrected, if you've remove most of bulk from the magazine aluminium would be ideal.
Beautiful, personally , I'd have the serial no plate laser cut and engraved as it would do the piece justice ( see what I did there play on word's ... oh please yourselves!!) joking apart.
A similar laser engraved perspex sheet , with a backlight Electroluminesent sheet would fit nicely inside , with a small hidden push button switch to turn it on/off , would make it perfect. And being all metal , it could be 'parkerized' ( gun blued) to make it absolutely spot on with the hero filming prop.
I so want a set of parts Please .. and shipping them as all parts ( not in one kit - obviously !!) should not break the rules on the act so , you should be able to ship to UK and all Europe member states. It just makes it a bit more fiddley!