Parts/Spares Wanted | Wanted: Power Adapter for ROLAND R5

I need a power adapter (PSU) for a Roland R5 (or R8) drum machine.
The model name is ACH 230 (ACH230) or ACH 240 (ACH240) or ACH 240e (ACH240e)
Basically, a UK or European one, on 230 or 240v would be fine.

Roland ACH 230 Power supply

Bloody typical Roland. Why can’t they use standard PSUs?
Apparently, the 3-pin plug has +10v/-10v/0v pins.
I can picture the Roland Sales meeting now: “Let’s make our PSU so complicated that we can charge fifty quid for it, and they’ll have to pay, because no-one else will make them. Result!”