I popped into my localish breakers to see if they had any rear Sierra calipers to fit to my XR4x4 rear end when it finally gets glued under my car. They didn't have any but then I spotted a Diahatsu Applause with no wheels on. It had discs on the rear. A closer inspection revealed a handbrake that works on the caliper. And they look to be fairly small. Small is good as the discs I had on the Atlas axle were far to efficient for my car.

So, has anyone used such things? I'm collecting them tomorrow so I'll let you know how it goes!