Greg is correct ,back then double crest bars without the model identifier were most likely #65 or #67. I did have a pair of #63's that were stamped that way. During this period the bars also had a model number stamped at one end. Often this was cut off by the user/ mechanic. For styling or "light weight" purposes.
Remember this is a "team" bike the bars used were to be the riders' preference.
John Jorgensen Torrance Ca today.
When once I found #63 bend bars, wanted nothing else back then on the road. #64's are just way too tight a bend for my palms.