Skyrc speedo repairs

[Mr_E]

Bought a Skyrc Toro 120a speed controller from eBay last week.
Wired it up and it was working great at the club for about 7-8 minutes when it just cut out as I was coming onto the straight. It is now totally unresponsive. It doesn't respond to anything. No fan on, no lights etc etc. Tried different batteries and it does nothing.
Seller I bought it from has said to get it repaired and they will cover the cost. (I have already asked for a refund or exchange but they want me to go down the repair route).

Does anyone know of anywhere in the UK that repairs these speed controllers?

Cheers
Paul