Hi Steve, I recently had a cylinder gasket kit from padocks, whilst i can't comment on the gaskets I can tell you that the injector o rings and copper washers looked very poor.
You could see a seam on the O rings with even a piece "extra " material still attached to it. The copper washers had both a smaller outside and larger inside diameter, making them a very sloppy fit and according to a local expert prone to "burning" through, resulting in exhaust gas presure in the fuel system. I don't recall if they offer gasket sets but Turners engineering do everything else and I have heard that they are good quality. I will be very cautious of Britpart in future and try and avoid.