Where to buy plain, unpainted cabinets / units?

[QuimReaper]

I can't believe I'm having this much trouble with this, but my builders have asked me to buy a wall unit and two base units of specific sizes, and they will paint them for me. But I can't seem to work out where to buy them from that they're not already painted / treated. It should be a totally straightforward purchase so I am probably being dense. Any ideas?

Thanks!

My brother got his from Solid Wood Kitchens - they have show rooms across the country. He has been delighted with his.
Kitchens to paint He actually got his ready painted in the end, but they can do it either way.

Thank you ThisIsSunrise! They are lovely, although very pricey!

If you can wait, Handmade Kitchens of Christchurch do all of theirs unpainted - but they're made to order.