My dating "guess" is late 1950's to early 1970's based on the spacers, which I feel are burgundy, 3 thick, 2 thin. I can not help you with the pinned butt cap. Don't recall seeing one before and I can't find any info in my notes.
_________________________
Rod Brown RKS 3846 RKCC CM-123 Whether you think you can or can not, you are right.