Miller single trigger

[RJ Jose]

Hi everyone, I've been a member of the board for a short time, but I've been reading and learning for several years. I own several Parker's, all 16 ga, the fever has not spread to other gauges yet but I feel tempted to expand my horizons - no cure for Parker flu.
My question is, does any one have any info on the Miller single trigger? I have a "O" frame 16 that I'm trying to mold into the ultimate grouse gun. Don't worry, the barrels have been cut to 26" from 28", leaving open chokes. Someone has fitted a Trojan stock on it with homemade engraving and bondo. I have a period correct "O" frame stock to fit and I thought while I was at it, I would convert to the single trigger, something I'm used to and like on my grouse guns. The trouble I'm having, is that I cannot find hardly any info on the internet as to history, fitment, availability, etc. I know Turnbull use to own the co. in the '90,s but no info since. I,ve noticed many doubles fitted with this from European shotguns to the American classics. Are they one size fits all - hard to believe, does frame size make a difference? What is a fair price if I find one at a gun show? Who is the Miller Trigger guru?