The original Windom antenna was fed with a single wire and was worked against good ground. It appeared similar to the OCF dipole because they are both fed at the 1/3 point. http://www.dxzone.com/cgi-bin/dir/jump2.cgi?ID=15689 The two are NOT the same. Windom =/= OCF Dipole.
The BALUN you'll need for the OCF will depend on the height you can hang it. Up to about 40 feet or so, a 4:1 will work fine. At 50-60 feet, you'll need a 6:1. In any case, you WILL need a 1:1 BALUN immediately below the other BALUN, or you'll have more RF in the shack than you'll be able to shake a buddistik at.