Based on SIG Sauer part nomenclatures, the answer would be "ONE" SRT in that pic.
Utilizing the OEM part nomenclatures in our discussions would benefit clearer communications and reduce confusion. Admittedly, that was the point of this thread.
Well I'm glad we can put this one to bed!!
I think there's a tendency at SIG to openly address only the occasional serious problem, and make notifications or recall only if not doing so might bring liability to the company. With lesser issues, CS will often seem clueless, "Ahh, umm, haven't ever heard of that before." And if fixes and changes are finally made, they come with no announcement or fanfare, CS get's a script to answer inquiries, "Oh yeah, that! We changed that part last year, the new one won't cause guns to shatter sending pieces in all directions - return the gun and we'll fix it, you have to sign a non-disclosure agreement not to tell Glock."
The designation "SRT", was "cleverly"

used for both short reset trigger & short reach trigger, spawning consternation and confusion with more than a dozen SIG customers. You can imagine what went on in the boardroom, the finger pointing, denials, head banging, the indecision as to how best to move forward - "How could this happen? What the heck can we do to fix this without Glock getting wind of it and making fun of us! I say first thing, let's fire someone. I told you we should have made that part with MIM!".