This is a GT5S with the later wider European rear valance panel, the license plate lights are very different than the Ford era cars.
I would try Roland Jaeckel
http://www.jaeckel-partner.de/en/detomaso
I think Simon Vels in the Netherlands went through this same search a few months back and I seem to recall www.reoriginals.com but the website is down right now.
Julian
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