Hi Denny, K is October. Ford used letters A-M for date codes skipping the letter "I" as it could be confused for a "1". ;)
RC sounds like a really nice car!! Most FE's these days you find are pieced together. With rebuilds, warranty and service replacements very few you come across are original. Hey good luck with the ol Gal... 62's are sweet rides!!
These sites might have the weather stripping you need.
www.dearbornclassics.com
www.gregdonahue.com
www.critesrestoration.com
Crites might not have it but they have some cool parts.