I think I've seen it going for not that much... maybe around 15 euros.
Since they were Dutch, I'm sure the easiest place to find it would be in The Netherlands. Your best bet is probably Da Capo Records in Utrecht, because they have got tons of 7-inches, much much more than they have listed on their site:
http://www.dacaporecords.nl/
They don't keep an up-to-date online database, but sending them an email wouldn't hurt I guess.