Just as an add on to "none of my bikes run" , I've done this a few times to some fairly rotten bases for 3 different bikes including my DT360, but you're better off glassing the side the foam was on it'll protect the remains of the seat base from damp foam in the future , all the features are still visible to refix rubber bumpers and brackets and so on , its worth getting woven roving as it has a neater finish , I know you have no base to work with Anthony 44  but don't pass up something you could easily bring back to life....

Maybe get some measurements from someone on the site who has a good pan and see if any of the pans KDI has are close. I know Dave has the 74 250. Maybe it’s just a bit long but could be shortened or an earlier model. 

yeah id never spend 100$ on that, hes crazy. what i did just spend 100$ on though is silencer piece for the exhaust for this bike. one came up on ebay with the baffle in it and its in great shape. the only other ones available were 300$ NOS without baffle. Last thing i need is this seat pan and my ignition kit so ill try to make somethin without the original pan. main concern is getting the pins and clamps to line up to atleast get the thing to swing open and closed

Offer him $50.00

If the edges of the pan are good, and it looks like they are, then that isn't a daft price. As Ht1kid says, offer something lower first.

It also looks like the protective strip that sits over the edge of the pan is still there.

If it is the same company previously made reference to on this forum, then the seller, bikeboneyard, are fairly well regarded.