I'm from the UK , so that link doesn't work for me.https://www.amazon.com/Corsair-Bron...dchild=1&keywords=Cx550&qid=1590202407&sr=8-3
Dude, please lol. That's brand new in Amazon. You can find them and the other pre-17 bubble labels all over the Indo-Asiatic markets as well as eBay in the States.
There's plenty of reviews about the Seasonic Core, the GX is a revamped Focus Plus, the GM is a revamped Focus, but I'm not sure exactly what the GC is. I'm sure there's a couple of fixes and tweaks, like putting the in-line caps actually inside the units instead of in the cables, but otherwise pretty much similar.
So like this one ?
A CX 550w yes. I'd not use a CXM, it might be nicer to be modular, but the stuff inside isn't as good as the standard CX.
The pics are a psu that must be a 10 year old design (that's for sale right now at a seriously excessive price). When choosing the CX, make sure it's the black/silver unit, not the big Green/White lettering like above.