This hardly qualifies as electronics, but I'm looking for a controller like the one in the photo - taking two 1.5v batteries and supplying a variable current a dial. Any help welcomed. I'm in the UK, but happy to buy worldwide.
I think that closest thing you can get is those controllers for the circle RC models
Search 1.5 PWM controller or 3v PWM controller or step up to 6v PWM controller if need be.
You can defiantly get 12v PWM controllers and put 12 batts in series.