AMT offered the first 1/25th scale 289 Cobra models (plastic kits), and it has been re-issued several times over the years, including under the new AMT/Ertl brand. It's a slab-side car that offers decent detail (but is a semi-difficult build).
If you are looking for an FIA, check out
www.scalecoachworks.com. They make a resin conversion kit that you combine with a few parts from the Revell/Monogram 427 S/C kit. To my knowledge, the diecast companies have yet to make a 289FIA car in diecast, but I know Exoto has plans for one in the future.
Russ