I have an early model JT1 (that I’m doing an as-new restoration on) that uses the flat filter element, and am having no luck finding the boot (gasket  under the filter housing that the fuel, oil, and vent hoses go through, as well as the flat filter element. Also, I’m searching for a nice original kill switch. Do any of you guys have any of these pieces to sell or know of a source for them? If so (and hoping this is allowed) hit me up by text @ (254) 730-1396. James

Uni Filter makes sheets of foam in various densities and thicknesses.  You could probably cut your own element..

Kill button is same as early AT1 starter button so that might expand your search...  they are hard to find and can be pricey.

Not sure where to get the rubber piece.

They have the whole filter and housing with the rubber NOS on eBay expensive but I would get the filter element  as MarkT said and cut out your own rubber with holes if you have the housing