The amount of installation required makes it pretty unlikely you will find a rental oxygen system for a private glider. Oxygen cylinder sizes are very glider specific. The most likely solution would be to buy a bottle that fits your glider and borrow an MH system from a buddy that isn't using it. If you really don't want to spend the money on a permanent system, the hang glider systems are portable. Or, just face the music and buy an MH system. They're great, and once you taste flying where oxygen is needed, you will be back. It also adds to the value of your glider.

John Cochrane