I've heard good things about ALG brand triggers for AK, AR. Here's a guy who said he was successful with ALG setup on his Saiga 12. He did have to remove material to make it work though - I would not recommend : http://forum.saiga-12.com/index.php...kt-trigger-in-converted-saiga12-sbs-it-works/
* Maybe a simple polish of your factory fire control would be best so as not to complicate things
When I did my Saiga 12 conversion I used a TAPCO AK trigger/hammer. I remember having to remove material from each side of the hammer where the pin goes through to fit it.