Weather Stripping?

Frnknsteen said
You might also contact Steele Rubber. I was just watching My Classic Car last weekend and they had a rep from Steele Rubber on there saying that they custom print catalogs for people based on their individual cars for all the parts they offer. They also have a bunch of universal options for weather-stripping in case they don't carry what you need.

I just did a quick search for a '66 Dart Hardtop and a bunch of parts came up. I didn't see roof rail seals, but it may be worth contacting them and seeing what they have to offer.

www.steelrubber.com

I contacted them for my 66 Barracuda... That custom catalog was lame. Very little in there. Metro, Vans Auto, Laysons, Year one.
A lot of places to buy this stuff. Check Ebay also. The hardest part si knowing what to call this stuff.
I typically if I have 1/2 hour will get on Ebay and search for example "66 cuda parts" and with that 9 kajillion parts come up and just scroll thru them. I've found stuff i could not find elsewhere or more importantly names and part numbers. From there you can find a search way easier.
Good luck.