Nope, but if it's the 78 with the custom paint at Super Sports and Imports, it's a consignment, and has been there off and on for over 3 years. Grossly overpriced, needs everything to be "nice". I believe the last time anybody I know asked about it, the rear louvers had been stolen off it.
As for rarity, total Cobra II production was around 45,000 units, in a Mustang II run of 1.1 million, so they weren't super common even when new, but are more likely to have survived than the "average" non-specialty II.