>>23384548
Yeah, given the colouring I assume it's actually straight up an HGUC shield. Comparing to the original lineart of the El-Ahrairah the shield's a bit too small for the body but not by a huge amount. The top of the shield should be nearly even with the head, and the bottom even with the knees. Course that's just referencing one piece of art and god knows how troublesome that can be.

Barzam II with shield booster height comparison