fuel tank pick up gasket

I have a 94 Ski Nautique. I had some fuel starvation issues. Checked my hose connections for any leaks. Pulled my gas tank. Checked the anti siphon valve (it is fine).The fuel tank sending unit had a cork float! But the debris from that seemed to mostly float on the surface (it did not survive being removed). I pulled the pick up tube assembly. The filter on the end had fallen off. There was a bit of debris on the bottom of the tank which I suctioned out. It was mostly small black particles. I have a new fuel/water separator cartridge that will be installed. There is a 1/2 inch thick by 6" foam gasket that goes on the bottom of the pick up assembly to restrain it in the molded tank. I have looked online in vain for this part. I have considered purchasing appropriate material from MC Master Carr to make the gasket, but the most promising materials are really expensive and only come in larger sheets. The foam gasket is definitely deteriorating and is probably what I'm finding in the sump molded into my tank.. I really don't want to put it back in the tank. I am hoping that I might get some guidance as far as availability of this part or a suggestion for a proper replacement.

Hmm, maybe running without the foam would be a good idea. Doesn't appear to be designed to keep the pickup assembly from moving and I don't run to empty anyways. 1/2" Buna-n foam rubber only comes in larger sheets (big bucks). Viton foam  would run me $146 bucks for a small sheet. I can get 60A shore viton rubber sheets in small sizes for something like $26 bucks. Not sure if that will deform enough to fit. WTF :)