Extractor replacement question

I have a nice 1959 Argentine Sistema, a 1911A1 copy made on Colt machinery, as most know. I had some ejection problems and need to replace the extractor and want to make sure I purchase the correct one. The series 70 government model should be the one, shouldn't it? Are there any manufacturers to avoid. Any help would be appreciated, I love to shoot the Sistema, but I am no 1911 expert.
TIA

Wilson combat makes a nice drop in extractor, and ejector, stay with standard parts,
and spend the extra money for drop in type parts.
cant go wrong with new GI as well.
i have a few new GI ejectors, maybe a couple extractors i might part with.