Hi i purchased a Roland MDX 20 hobby milling machine from ebay ... I was told it was in good working order but when I received the unit the milling spindle carriage is jamming this is jew to plastic teeth on on of the drive gears being worn out .... I tried to get my money back but the person has done a runner ( my own fault for being trusting ) anyway can anyone tell me where i can purchase a new or used gear in the UK please