eBay seems to be full of stuff that looks like a bargain but as said above there are loads of cheap copies on there.
I wasn't prepared to get caught out with a cheap copy so bought my Turbosmart FPR800 from Autodynamix as a cheap copy could cost you a engine.

I bought a Tilton bias valve from eBay which was nice and cheap but turned out to be crappy copy and leaked out the adjuster valve when trying to bleed the brakes so ended up buying another one from a online shop at the normal price.

They say buy cheap buy twice and I can confirm that what happened so be very careful.