For the last two years I have been supplying a three layer sandwich plate gasket which replaces the original metal item. They have a stainless steel mesh core with Graphite facings both sides and are made for me in the UK by a large gasket maker specialising in the nuclear, petrochemical and pharmaceutical industries. I supply four of the main service specialists for the VX220 in the UK as well as private owners around the world with well over one hundred pairs now delivered and a 100% reliability record. I also supply a Viton O ring for the smaller filter cap used in this installation, like the gaskets no longer available from GM. The cost in the UK is £15 for a pair of gaskets, £2.50 per O ring and £4 for the postage for up to four pairs, five pairs or more are post free. Please PM me if this is of interest.