The Diahatsu Hijet is/was available as a 4×4, but to be honest you’d probably be glad of a bit of snow as an excuse not to drive it 😉
You could also look at the Citroen Dispatch 1200 XTR+, medium size van (smaller than VW/Transit), its not a 4×4 but it does have a limited slip differential so unlike most vehicles you won’t get stuck with one wheel spinning away on a muddy verge whilst the other is sitting on the tarmac doing nothing. Probably not got much benefit over a 2wd drive van with traction control though.
Seeing as you think you would be OK with a small van you could also consider the Ssangyong Rexton and Mitsubishi Outlander GX1, they are commercial versions of passenger cars. Rear windows are deleted and obviously no rear seats.