28 Mar 2011, 09:56
Not sure about a manual, you may want to try the A904 Seiko manual on the site, its a very similar layout. For the year there should be a long serial number on the back, the first digit is the year and the second the month. For instance the serial number starting '85' The year would be either 1978, 1988, 1998 and the month would be May. If the second digit is either 'O', 'N' or 'D' that would make the month October, November December respectively.
regards
Adam