Clicks will tell you, but so will the number stamped on the shifter.
Dura Ace:
7400 - 6 speed
7401 - 7 speed
7402 - 8 speed
I suspect it is either a 7 or 8 speed based on anodize color. You can friction shift them. If you index them with a non-Dura Ace rear derailleur you will need to do an alternative cable routing... which I do.
John