......came across some stainless steel air vent escutcheon plates.
Not quite sure what you're looking for, something like this maybe ?
https://www.ebay.co.uk/itm/321416166973 I have some in "doll's house" size which I have had for years but never really found a use for them. And dishwashers have nice perforated stainless filters, perhaps you could raid one from the Tip ?
