I got a replacement board from Stellatech in Europe. Part link. It cost 7 Euro's plus postage and VAT. I have just replaced the small board in the watch and its happily charging. Once I had taken the case apart (Thanks iFixit! teardown link ), I used a small spudger to pries the board of the base. See here for an image of where to prise from Its glued in (I assume to keep it water tight) and take a bit of effort to remove. Pulling by the little Tab actually separated the board from its backing! I used a thin layer of contact cement on the base. Lets see how it goes.