Hi Danny and welcome to the FISD
Judging by the lid it looks like re-cast FX !!
Just to also make it clear the 501st do not give their approval to any type of Armour, it is totally down to the construction.
There are a couple of company's that are using the words 501st approved to try and sell their goods. This would give me cause for concern as to the quality of the end product.
Armour like TM, RT-Mod etc do not have to use those type of words as the product sells itself by reputation alone.
Danny, I wouldn't touch it mate,
Check out this thread to give you better insight to Armour suppliers and where you can get it.
http://forum.whitearmor.net/index.php?showtopic=11538
Also check this as well..
http://forum.whitearmor.net/index.php?showtopic=18488&pid=225650&st=0entry225650
Besr of luck mate