I may give it a go.
The top of the mould could have a light cut taken to smooth it. A sprue plate isn't that much from Red River Rick. Heck, I may even give it a go to make one.
The screws for the handles could be an issue but if need be could be milled off. New holes could be drilled and tapped near the old location.
Cavities could get a light polishing to see what they can do.
I don't own an 8mm so I may need help from Ben on that part.