OK, come the new year I am having some work done on some stainless flanges, by a new firm of engineers I found by chance.
Also does cash in hand work

so I'm looking at having cover made in either alloy or stainless, as this original plastic part gets totalled in a right hand spill, I was thinking of having the flat surface extended with a sacrificial easy replaceable part.
Any interest would bring down costs, and any thoughts would be good.