Hi, yes I'm in the UK too and you're right about prices. I'm shopping at the places you mentioned also. Sometimes bargains can be found in the advertisers in EPE Magazine.
I'm planning on using an open frame toroidal Xformer for my PSU. Should be fine for you also.
My design is for running...
I am also building a power supply with current limiting. For the current limiting feature I'll be using an SG-3524 Pulse width modulator and a low ohmic current sense resistor, 0.05 Ohms.
The basic theory is: Voltage drop across a low ohmic resistor is directly proportional to the current...