Washer/Gasket for Petrol Tank Sender Unit

[abrogard]

I've got a '71 XY Wagon and I've had to take the sender unit out of the petrol tank.

I see it used to have a washer there (or gasket, whatever you want to call it).

Now I've got to put it back in.

I don't think I'm going to find anything to suit. I'm going to have to make something up or go without, just use goo.

Anyone got any ideas what would be the best way to.

regards,

ab