Not sure, will need to have a look around at the invoices I have. I recall getting in touch with the local distributor of Champion plugs, and they pointed me to a local supplier. When I contacted them, they thought I was a parts shop and quoted me disti prices and delivered them to me...they made a mistake by assuming I was a trader, but went through with the deal anyway. I was impressed by their service and naturally the price.
Will see if I can find them.....otherwise have a google hunt for the local Champion distributor and call them up.