Generally speaking, Not Available printings beyond the 1st have a datestamp on the front or back cover which is the printing date of the batch that copy was from. Matt Feazell says those post-1st printings were usually 60 copies or fewer.
1st printing appears to be May 1984.
Other known printings:
March 20, [no year on datestamp]
September 18, [no year on datestamp]