almost all of these cars have been rebuilt and are owned by "fox body" devotees....best option for you if the car is nice/good shape is to get on a forum for fox body mustangs...
like here maybe
dialogue with other owners , maybe even post it for sale there.
biggest issue is overall - what is your car like, if its a jewel & stock cobra could be worth a bunch, rust bucket and barely running, hundreds....(have a look at e bay motors)
heres a couple of 79's on craigslist , but neither are cobras
good luck (04 cobra)