Hi Mike, welcome to the forum. There are a lot of these little items that are going to be found at a swap meet or salvage yards. Overall, these cars are not that difficult to find parts for, but some of the items, like you are asking for, aren't aftermarket produced. Maybe one of the other guys on here has one available.
here are a few places I've had luck finding A body parts:
(you never know what pops up there)
(very nice swap section in their forums)
(decent A body swap forum)
I have dash parts for a 66 GT but not for an AC car. I had a 1966 Dart GT slant six car from the Los Angels plant and it was a radio delete and a heater delete car. If you like I can go through what I have to see if there is anything worthwhile to you. Not a huge amount of stuff.