I would suggest the toyota hi-ace, you have a choice of the 300 (lwb), which has a payload of over 1200kg, and the 280 (swb), most versions have a 1135kg payload. The reliability is legendary (bear in mind, the hi-ace is mechanically nearly identical to the hi-lux pickup they unsuccessfully tried to 'kill' on top gear!). Usefully narrower than transit/vivaro, and rear wheel drive gives good traction without the very high load floor of rear drive transits.