I think the remote mirror is the same as a Mustangs.... in which case Mustangs Unlimited do repo's and i can vouch for their quality of service!! Otherwise try Cougars Unlimited.... they might have an NOS/repo one lying around?? They are alos very good to deal with!! Check out the links pages.
Not sure what you mean by "ends". The only part that is different is the part that screws to the door.
It is possible to buy a repro 67 Mustang remote mirror and use it to restore a 67 - 68 Cougar mirror. Note that all the available repro's are '67 style with the "bat" handle rather than the "ball" '68 style.
You just have to have the Cougar mounting bracket rechromed, then use the mirror, cable and head assembly from the Mustang repro. The hard part is carefully prying apart the knob where the three cables attach without breaking it.
just out of curiosity, how hard are they to find? i have 2 67 remote mirros lying around, but both are kinda pitted. just want to see if they are worth rechroming or if id be better off finding others out there.