[Slotcross]

Having looked at the options, my first choice would be Truspeed, but the club track one is out of stock.  Can the wires from say, the Scalextric analogue jack be reconfigured?

Should have said I already have a 10A variable PSU.  

Otherwise probably the Slot.it SCP-2 Universal Analogue Electronic from PSR.  If that's the right one. 
Only want wired. I'd like to be able limit speed to scale/purpose.  Stock levels appears to be an issue.