Inimbrium

Hi I have an old parts assembled a skywatcher 250-1200 OTA (the old blue variant) on an eq-5 to form a nice telescope for under £300 if you can believe it, that I built over the years but can't afford to buy parts as new. I do know it's underpowered, but it's the best I can do given my income. Maybe one day I'll get an eq-6 for it, but not anytime soon. Worst case I'll downgrate the OTA to something lighter, but I still need a goto kit. So the question is: Where to buy a cheap second hand EQ-5 goto upgrade kit such as Synscan or similar? It would be nice if there was an android app based system over bluetooth or wifi or something but any goto with a library and an lcd display will do. Inimbrium