I want to replace the trigger on my ruger sr 762. The question is will any AR 15 trigger work? Such as the cmc AR-15 trigger offered at Cabelas??

trigger sear and springs are usually different for the "AR-10" type rifles.
I would go with a trigger designed for "AR-10" / DPMS308 rifle.
I put my Timney AR15 and DPMS308 side by side and they're different.

The CMC triggers should work. I'd give CMC a shout to verify, but I have one in my .243 build and it works fine.

Many AR triggers will fit either the AR-15 or an AR-10. If in doubt, you can go a website like MidwayUSA and look up the trigger you want. It will tell you what model it fits and applicable pin size as well.

My DPMS 308 takes the same trigger group as the AR-15. I swapped mine out with a Rock River 2 Stage Match and it shoots perfectly.
I can't speak for the Ruger though.

I have a CMC and a Geissele in my Armalite AR10 rifles. I'm very happy with both.

I like RRNM two stage triggers with JP springs.

Geissele SSA-E in mine

+1 for CMC