Was this a fake clasp spring?

Happy New Year, all!

So a couple months back, I replaced the clasp spring on my Speedy because it started feeling loose and you could open it by only pressing 1 of the 2 push buttons. I ordered what I thought was a genuine clasp spring from eBay. Seller had high feedback and packaging looked consistent with the Omega parts I've seen.

For the past couple of weeks, the clasp has been extremely difficult to close and one of the buttons started feeling mushy. So I took it apart today only to discover the spring is rusting, meaning it's not stainless steel:



I happened to have kept the old clasp spring and here is a shot of the packaging (I opened it) and the old spring (right) being compared to the replacement that has rusted (left). As you can see, the old spring had a polished silver color while the new one when it was new had a rough gray finish.

So my question is.... did I buy a fake clasp spring?! Part no was 085ST0056. Did Omega decide to stop making it out of stainless steel at one point? Watch was never exposed to sea water.

And no, it wasn't wrist cheese. Had to bust out the WD40 with a toothbrush to get the oxidation off the clasp

I haven't and it's been a couple of months (August?), so I don't even know which seller sent it to me. Doesn't show up on my Purchase History.

All the packaging seems to have a smooth silver foil on the inside while mine had like a diamond texture. There's another for sale (not the seller I purchased it from) for the lowest price on eBay of $38 and it has the same texture.

textured packaging like mine, currently being sold on eBay for the lowest price (different seller)

smooth packaging

could be a factory packaging variation... I have no idea

Ever seen one rust like mine?