RE: Glider Info
It does seem to be pretty rare.
The advice given on the other forum also seems to be somewhat dated. MOF, it's dated 2004.
The idea that 10 cells are required shows that as well. There is also very little value in having a geared power system.
Nowadays, with LiPos and brushless, you'd look for any motor that'd simply fit into the nose as the first step. There are going to be hundreds that'd fit, so you look at the weight of the glider to decide on how powerful you'll need. Then pick an ESC to match the amp rating of the motor and a battery with the number of cells to match the motor rating.
There are so very many combinations possible today that there could be thousands of solutions. Have you weighed it to see what you're going to be dealing with? That's almost always the starting point for powering gliders that vanished from the shelves before brushless and LiPos showed up.