Here's some REAR END CHOICES Being in the UK may present some issues finding these. I know when I converted my 53 Suburban years ago, I used a passenger car rear end with 5 lugs. I had to weld new perches on the rear end and make sure i centered it correctly in the wheel wells.

I am sure there are others who have installed later model rear ends on the art Deco series truck, they will chime in.