This looks like a nice one. Relatively low miles. Manual transmission. Looks to be in nice shape inside and out. Under the hood is detailed as well. The seller notes that the top should be replaced. There are no pictures of it but my guess, based on him stating that he never takes it out in the rain, is that the top stays folded all the time. Buy this, replace the top and park it with the top up!
https://pittsburgh.craigslist.org/cto/d/cheswick-ford-mustang-7up-convertible/6889293795.html