Every well sorted model railway shop in Germany does carry the very wide Preiser range.
Since you live relatively close to the border, you could visit one or more shops on your next trip to your eastern neighbours.
Anyway, quite many german (& some of the bigger european) online shops sell Preiser as well.
A simple search on the web might do the trick already.
As far as I remember, Dragons Cave, Kamar, Tracks N Troops, Jadar and MC Modellbau offered 1/72 Preiser sets in the past.
Again, the easiest way to get hold of your desired sets may be to search for online railway shops ("Modelleisenbahn" or "Modellbahn").
Because Preiser is primarily producing H0 (1/87) railway figures, its particularly those shops which offer their whole & much wider range very often.
Shipping to the Netherlands should be within tolerable limits.
Hope this helps?
Good luck with your hunt!
Edith says that Jan gave an appropriate answer in the meantime already.
Well, that happens when you're trying to do 10 different things at the same time while being online...