The triangle glass part is held into the actual metal frame with the black window sealer goop. Ask around at a local automotive glass shop, what the best goop to use for your area/climate or how much they'd charge just to reset the glass back in place, cuz they have tubes of the stuff just laying around in multiple caulk guns. Same goes for the big side glass in the door...
For the pieces that go around the outside... of the frame/glass...
look at the
various vendors, they will be listed under weather strip, glass or door parts : vent window weather strip for 1964-1966 or some other similar term, depending on the vendor.
If you want to know how to replace 'em, see the vent window rebuild thread listed in the 60-66 FAQ Index.
Good luck,
-W