Greaves will get my vote.
I'd certainly put Smith, Chivers and Gilzean on the list. Gilzean was considered for the #10etc role but that was partly because he was up against Greaves for a single striker spot. He was bought to replace Smith as centre forward and was very much part of a striking pair, with two excellent partners, with us.
Then it depends on how long the list is. From our history there is a good case for Woodward, Duquemin, and Hunt. Then Defoe is in on numbers and its hard to pick him and not Keane.
I wouldn't pick Lineker, Allen (Clive) or Klinsmann based on longevity. Klinsman (38 goals) didn't even out score Perryman (39) and Mabbutt (38) in our shirt. Allen is the closest, because of the wonder season and strike ratio, and perhaps his 84 goals is enough to make the shortlist if we are going for ten.
A special mention should go to Archibald and Crooks, who were a great partnership with us. Together they deserve mention alongside Greaves and Gilzean, Chivers and Gilzean, and Berbatov and Keane.