How many copies are you talking about providing an hour after the event?
Get a good set top recorder and feed your signal into that. When complete finalize the disc and pop it into a tower duplicator that also prints. Google for info about duplication towers. They vary in prices and speed. You might be able to rent one a s well. The key to something like this is planning and preparation beforehand.
If your talking about menus then thats a different story and might take you a little longer but if your prepared for the workflow it won’t add on too much time.