My questions are about this model:
SIG SAUER 1911 Traditional SS Match Elite

!. Does this pistol use a series 70 type firing system (no firing pin block) ? If it has a firing pin block, is it activated by the trigger or grip safety ?
2. How many of the parts are NOT common 1911 ?

Series 80 for all Sig 1911's. activated by the trigger. From my knowledge the only parts that are not standard parts as most 1911's are the external safety and the slide itself which is Sig's design.
The series 80 is not even noticeable as I could convert it easily to a series 70, but I found no need to do so.

Keep in mind that most Sig 1911s have a larger and boxier slide than a standard 1911. As a result, they won't fit in many/most 1911 holsters. You have to look for holsters specifically produced for the Sig 1911.