basically any 4 cylinder engine will fit comfortably. There are photos here of 6 cylinder engines in 120y's as well as a v8!

I'm not too sure what kind of engines you have in holland. Find something that is reasonably cheap, has a reputation for being strong/reliable/powerful, with plenty of avaliable performance parts.

An SR20DET would be nice, and it would quite easily make the horsepower your chasing, with plenty of potential for when the bug bites, and you need more power. CA18DET is cheaper to source (in Australia at least) but requires a bit more to get the same amount of power. These are among the most common swaps into datsuns in Australia, but maybe you have another motor there you could use?

Just make sure that any swap you intend to do is legal if you intend to drive it on the road, and make sure you have the money and the know how to finish the project.