At my current location in Europe, low cost items usually pass through customs without a lot of extra tax, although sometimes it comes down to luck. Should be 20%-25% total if they decide to tax it.
On a sidenote, the seller I linked to is flexible about what price they stick on your package. You don't want to overdo it though, otherwise you might end up paying even more tax than normal.
I don't know about Netherlands, but in Spain you can contest any customs tax. They send you a printed form to fill if you want to contest it in the same envelope where they send you the invoice for the tax. Things can't be very different there.
On a sidenote, the seller I linked to is flexible about what price they stick on your package. You don't want to overdo it though, otherwise you might end up paying even more tax than normal.