I'd prefer he didn't need it either. But it's too late for that, so thankfully I was already working on prosthetic arm technology for months, which puts me ahead of the curve on his.
We can definitely talk prosthetic technology. It's mostly rooted in Galra technology from my universe because it's what I know / have access to mainly. But I've been watching/reading about other universe's prosthetic technology in order to pull that in. And I've been discussing it here with the dwarves (particularly in regard to mithril). Anything that makes it specific to Keith's arm, I'll let Keith decide who gets to hear about that and not.