Thought I’d throw this one which landed today into the mix.
I’m certain it is made from two genuine component parts. The RND shoulder title is I believe an exact match to TRT’s.
The MGC element appears to be a less seen variant with an orphaned jewel or dot below the one in the crown’s central cross. High Wood has a very similar version in this album showing it’s age:
https://www.britishbadgeforum.com/fo...ictureid=56188
Obviously with a badge of such construction it’s difficult to be 100% certain but for £25 my feelings towards it are more warm and glowing than any urges to send it back.