What model year? Really it only matters as to whether she is a 1971-74 or a 1977-85 model. But anyway, Rudy at D&R Marine has the original O'DAY 23 Manual, at least for the later, 1977-85 model. I think he charges about $10.00 including postage. You can call him at (508) 644-3001.
OR, I have the same manual, but in booklet form. I also have the early 1971-74 maunal but it really deals with mostly operation of the original design pop-top.