As with any purchase- BUYER BEWARE.
Some of the parts of eBay item 380200049475 are extremely rare, but some parts are incorrect, which will drastically affect the value of the headset.
The seller points out that something is missing, (the "locknut race") but does not point-out that for example, the top nut is wrong and the upper (pressed) cone is wrong. The seller also refers to this set as a pista headset, which is incorrect.
Have fun bidding in the rarified air of rare bike parts, but equip yourself as best you can because there are sellers out there who either don't know their stuff, or are unscrupulous.
Bottom line- if this dude knows enough to say that he has rare stuff for sale, he owes it to the community to appropriately research his wares so that he can represent them honestly and fairly... THE LEAST HE CAN DO is qualify his description by saying "I think this is a..."
John Barron
Minneapolis MN USA