Don't panic Dany. Although I do consider Belgium to be one of modeling's mekka's, maybe it's a little behind on the vacform front. I got my kit from Hannants in London (went there on a pilgrimage
), who seemed to have quite a selection of kits. As you probably know, they also sell over the internet. An option a little closer to home (for me at least
) is the Luchtvaart Hobbyshop in Aalsmeerderbrug, near Schiphol. That shop is as big as Hannants (maybe even bigger) and stocks a LOT of kits. When I was there last I did see some huge vacform kits, but I wasn't really looking for any so check their website for info on their selection. Check the prices though. My Scimitar retails at 55 euro's from Hannants and 80 from the LHS now!
I'll add the links to the websites:
http://www.hannants.co.uk/
http://www.lhshop.nl/lhshop.asp
I just found Aeroclub's website, and they don't just sell their own products. Check it out:
http://www.aeroclub-models.com/index.html
I hope this will help you in your quest!