I thought I had added this one years ago, but obviously not.
This is a very clean Accutron RR model from 1976. It runs quite well but eats batteries as they tend to do. There was some talk a couple years ago about Bulova making the Index Wheels for these again, and even some rumours they were going to make the movement again, but as far as I know, this has not happened. There are few Index wheels out there and when they are gone, they are gone.
I see them being sold out of packaging on eBay, and this is not good. Simply touching the wheel with tweezers will destroy it.
Anyway, I don't think the expansion band is original, but it might be, it is a Spiedel.