You've sparked my curiosity. I have ordered these from different vendors and they have come with the correct collar. Even my local parts store. However it seems now that 2 vendors do not show collar in the catalogue any longer. Rick's First does show collar. You will have to call to verify product description depending on which vendor you prefer. It may depend on their supplier and the catalogue picture update. Regardless, the major vendors are not the only way to obtain parts. You may try: Master Power Brake http://www.mpbrakes.com/products/product_line/index.cfm
I have not used them so I cannot verify their reputation.