Larko64

Hi everyone, I've found a coolant leak coming from the coolant fitting at the back of the engine head. Possibly a bad gasket, but I've had the thermostat housing off recently and it was it pretty ordinary condition with pitting, so I'd prefer to replace coolant fitting altogether with gasket. Any suggestions on where I can find this part? I can't seem to find much online.... Any advice appreciated. TIA Larko