Hi, I have a portable electric oil Rad and it has started to leak oil around where the element goes in, have taken the element out and found the fibre washer perished so need a new one, the company that made it say they can't get one so trying to find one, which is proving difficult, does anyone know where I will be able to buy one, the size is : internal bore 43mm, external 55mm, width 7mm, thickness 2mm.