My New Yorker was sold with a dealer (aftermarket)installed vinyl top.
I need new clips so I can pop off the trim so as to paint the car. The very first one I tried broke so I'm not expecting good luck with the rest.
I have searched every automotive fastener supply company/catalog that Google can produce. Not one has even come close. Any help? Thanks.

If you can get ahold of an AuVeCo catalog I bet you could find something which would work.

In lieu of that, that trim piece looks to be about the same width as the beltline trim used on '71-'77 B-vans, so if you can post some measurements or the trim (where the clip rests) I can check to see if I have anything which might work.

The Au Ve Co catalog was the first place I went to.
Unless I missed something.

Basically, the back side of the trim is hollow and "snaps" onto the clip. There are no slots to allow sliding in the more common type of retainers.

Check out these two places:
http://automotive-hardware.com/auto-body-clips-c-14.html

I sent a similar style nylon clip to this place and they matched it for me:
http://northlandfasteners.biz/Store/index.php?cPath=288

With a bit of time, patience, a drill & a table saw, that looks like it could be duplicated fairly easily with some PVC stock.