Most likely from an old Great Western,their "fast draw" mdl. came w/brass trgr. strp. & bkstrp.-they were the 1st company that produced SA's almost identical to the colt,the parts were inter-changeable,a lot of their 1st issue sheriff's mdls had hammers & cyl's w/colts rampant logo on them.I still own a few of them.Saw a first gen SAA today at a gun show and it had a brass trigger guard, the fit seemed good, any idea what it came from??