Possibly a Canadian Cuda ?

64 was the only year that the Valiant, Plymouth and Barracuda was used on them, I almost bought one. The Valiant lettering was phased out for 65. The 64 I looked at had the push button auto, last year for it.

318 wasn't available in 64, I think 67 was the first year for them. 273 was.

Lots of irregularities but nice car nonetheless.