That pressure regulator, as well as the fittings on the bottom, that are not sold separate from the hpfp is why I continue to pop into my VW shop and collect all their used hpfp's. Senseless having to buy the complete pump for one attached item, right?
I was happy to help out...and I do appreciate the shipping being covered by Atreah (SP 
) 
Happy it's working as my only concern was it being a different revision...and could the limiting valve be changed from one revision to the next. I haven't been able to find where the reason for revisions to VW parts are kept...yet.
Ofc, I wouldn't want it any other way, other than me covering the shipping!
But yeah, the reason as to why you can't buy this item separately remains a mystery to me. Meanwhile, they'll happily sell you the bottom HPFP sensor. I mean, I know they're two different things, but heck, it doesn't look like there are any compatibility issues that would make the production of these as a spare part an impossible feat, even if there is more than one revision. I guess it's just "meant" to be this way.
