I have had very good customer service from Partzilla.com. They have live chat on the site which I found VERY informative as regards updated parts for the Gen 1 head cover (i.e. notorious valve cover leak).
Also, the Kawasaki specced sealant for the head cover gasket, TB1207B was difficult to find but Mat "The Flowmaster" dug into his data for me to find the right part and it was delivered quickly. Mat is one person you can count on if there is a problem finding the exact item you need to have. If you need his help, ask for him at the phone number on top of the Partzilla home page.