Original Cobra Jackets...
I have three original Mustang Cobra jackets that I got from my uncle, who worked at Ford, and got them new in 1965 or 66 when he bought a 65 or 66GT. Two are red, one is white. These are the same as you might see described on eBay as "Vintage Mustang Jackets".
They are all sized large, although they seem to run a bit small in size, so they should fit someone that wears a medium quite well also.
Condition of the white one is very good (still has a dry cleaner tag on it), one red one is also very good, and one red one needs cleaned at a minimum. Bear in mind that these are original and were new in 1965 or 1966 (best I can remember as it was a little while ago ). .
I can email pics to anyone interested, and am open to reasonable offers.