Oh, I didn’t knew the Spanish Base Set cards had both PI and PV. Does the PV only apply to the (Cosmos) unlimited edition Holofoil Rares, or have we also seen it with any non-holos? Makes me very curious if a PV Pikachu is out there. EDIT: @banks All Spanish Base Set are PI. That second Clefairy picture you’ve posted is Italian.. 
As for some of your questions:
Can’t speak for all countries, but yes for The Netherlands. I opened a few Base Set 2 booster packs and a Poliwrath Base Set 2 theme deck as a kid, that were bought at my local (Intertoys) toys store.
Yes, I pulled a Jolteon myself:
No’ish. They’re not 1999, but rather ©1999-2000. But the Italian unlimited edition Base Set Ninetales and Gyarados are available as both Galaxy Holofoil and Cosmos Holofoil, whereas all Holofoil Rares from the set are Cosmos Holofoil by default:
Source (which based on the bottom comment you’re already aware of 
): Ninetales base set holofoil error
Greetz,
Quuador