Alan Bean, Harrison Schmitt, Gene Cernan, John Young ?

[adamant]

Would it be possible?

[Count Fooku]

Bean and Cernan have done Autographica before and are active on the circuit in the US so its possible. It seems Schmitt is only really interested in signing his book these days and doesn't seem very interested in doing signing shows so I would say he is pretty unlikely though remains a possibility. John Young though I would say is an almost certain no. From everything I've read about him, I don't think he would be comfortable in a signing show environment and even if he was to do one I suspect the fee he would require would be astronomical (no pun intended!)