Hey Derv, glad it went together for you. These cars are pretty easy to work on once you see how they go together. Having one in boxes that you didn't take apart yourself could be challenging. Main reason I had started this thread.
I believe all hardboard headliners where white. The one I purchased was intended for the Plymouths. The Dodge ( 440 and Polara 500) had a foam coating on the hardboard (Bedford Cord) that no one makes and it was always beige. The white will look good on your red and black.
REM sells the hardboard that I bought and they should still make it. I don't believe they keep the cut pieces in stock until you order it. Then they cut them and ship them to you.
https://www.remautoinc.com
If I were you, contact REM and ask if they are still available and how much they cost. Then contact Joe Suchy (he's your '62-'65 go to guy) and ask him how much. Most of the time I found that a vendor can get them cheaper than ordering directly from the manufacturer.
View attachment 812740
I jumped around a little when documenting my removal and installation but it should all be there.
https://www.forbbodiesonly.com/moparforum/threads/taking-up-new-residence.114133/page-21
Take inventory of what you have to install one. I don't believe you'll find any bows, clips and trim new. You should find the bows and clips used. The plastic trim that holds the boards to the bows are being reproduced by a member on here. They aren't an exact match but it looks like they work.
https://www.forbbodiesonly.com/moparforum/threads/wagon-headliner-bow-trim.157729/#post-911041221