GM, has never made these parts, ever. they are supplied to them by ????? (roll, dice, check watch, phase of moon) and the older the vehicle gets, the less picky GM is with who they source from. I dont think you list the year but that list above sniffs as early-mid? 00's.
In todays world of global packaging there are often 4-5 maker labels on the box (trust me on this, my shop ran on the commercial parts jobber, not the stuff you get from O'vancezone parts. depending on WHICH box label caused your address to be used, sets what you pay. frustrating and pays to have a good jobber....
note on dealing with the rock - they dont use regional warehouses anymore - so get the target part number and if you are a prime member, plug it in to amazon. I hate for Jeff to get any of the money, BUT, you are oft actually buying the same part from the same supplier with shipping for less than rock+shipping AND you tend to get it within 48 hours unless its a hard stock and you live in in east bum-f. Lately, the little blue vans have been rolling up next day for stuff I woulda never thunk...
ps: check the warranties. too often today, the farther the maker gets offshore, the shorter the warranty is. the mexican/south american stuff aint bad. when I see 'china' on the box I sigh in disgust..
ps: genuine GM means (today) that the maker of THAT part is the same maker who supplied that run initially. with the demise of things like SSG and delco remy and hydramatic etc, the factory almost NEVER has the mark on it.
