There's not much this size on the market though.
Hi, there are a few happy owners of these rare B75s on the web, I seem to think the HUBB had a contributor with one for a while.
IMHO compared to the military work for which they were designed, you won't work it as hard as that.
With warnings like Rob's you know which extra spares to take along when you set off. I don't know who makes the axles/transfer case so can't comment on parts availability. At least the Renault engine & gearbox are well supported.
Volvo trucks now owns Renault trucks (they bought it for the engines) so the distributor network is effectively doubled.
Remember it's a mini HGV so expect to pay HGV prices for parts & service.