Another option are triggers from here.
Geissele Automatics, LLC. - Hi-Speed National Match Trigger
A few weeks ago at the local funshow i tried out one of the RRA match triggers,was not impressed in the least.LOP was fine,but it felt gritty,almost like it was full of sand.
Hopefully that one is not representative of what RRA is putting out now.
Ended up passing on the RRA and am now looking for a couple of the Geiselle' to finish up my varmint builds.
For around $40.00 Bill Springfield will rework a stock trigger to near perfection,a good alternative for a budget build.