Government funding
My own gut feeling is that Bussard would be better off staying away from government funding as much as possible.
Elon Musk put $30 million into the Tesla electric car project, and a lot more than that into his SpaceX launch vehicle.
I find it hard to believe that it's impossible for Bussard to scare up a few million from the private sector. His Google presentation shows he's at least trying.
