I took off a radiator in order to redecorate the kitchen. In the process of removing the radiator, I stupidly sheared off the brass top of the lockshield valve. Hence the valve is now firmly stuck in the "off" position with no way to turn it back on.
I've searched high and low for a replacement valve in all the big DIY stores and also in more specialist plumbers merchant stores but I cannot find a suitable replacement anywhere. It seems that it's a non-standard valve; it's a valve that includes the drain cock as part of the valve itself. There are of course similar valves with incorporated drain cock for sale in many places but the diameter of the pipe connections don't match the one installed on this radiator.
Can anyone direct me to a specialist store, either online or high street, to try and find a replacement valve? As the weather is starting to get colder our kitchen is getting cold too so it's becoming urgent! BTW I live in the Greater Manchester area.