Boat I saw today with the stuck keel was actually a ds22 not an O'Day. Pretty good shape.
You better do your research on this one. A stuck centerboard does not indicate "pretty good shape." It can mean 1) cracked and delaminated fiberglass foam core centerboard, 2) cast iron swing keel rusted all to hell and stuck (which I don't think is the case on a DS-22, but I'm not familiar with the boat. There's a guy on
www.trailersailors.com forum who has one, I think. Based on a quick interwebs perusal, I think the DS-22 has a centerboard, not a ballasted swing keel) and finally 3) Ballast in stub keel is encapsulated steel punchings that have been infiltrated with water and rusted and swelled. This is seen on the Montgomery 23...
Of the three options above, 1) is probably easiest to fix, 2) not so bad other than hundreds of pounds of swing keel to extract and move around for cleaning and sealing, and 3) is major surgery.