You are probably looking at about 300 - 350 fully comp if the van is only a few year old and you have full no claims. I would imagine closer to 200 if third party etc.
You could try the spanish compare sites on the internet. If you put comparativa, seguros and coche into google it should give you a few options to try. Hope that helps.

Catalunya Insurance Services advertise on the Forum site aswell.
Telephone number on their ad. is 977493607
But also have the following numbers: 977092043  977092044