The vendors, some at least, do keep burned-out, etc. cars on hand for parting out.
I know Larry Stock, Pantera Parts Connection, Reno, has some.
I'd call him, and the others, and see what you can turn up.
Larry
PANTERA INTERNATIONAL
A DE TOMASO CAR CLUB
Presents the De Tomaso Forums
The On-Line Meeting Place for De Tomaso Owners and Enthusiasts From Around the World
Clicking on the banner will take you to the sponsor's website.