Graeme formulated on Tuesday :
I don't think the Maplin units are available unused now, but CSE units are :

https://www.circuitspecialists.eu/power-supplies/bench-power-supplies/switch-mode-dc-bench-power-supply-adjustable-0-30v-0-5a-csi-3005sm/
;

Highly recommended. 10amp unit also available.

My Maplin unit recently took out it's voltage/current sensing IC,
repaired now and I suspect it was just an isolated failure of the IC.