One thing you could do is get a tractor/atv/motorcycle size battery and mount it somehow to the blower. Wire the light to it I dont believe that the light would draw so much that it would drain the battery. Just make sure to keep it charged and it should work fine.
I have a 8hp Toro. It has a wire with a strange harness on it for the dealer to supply an over-priced light and just plug it in. I'm going to cut the end off the connector and solder a wire from a 12 volt light to it. I'll put a in-line fuse but might not bother with a switch. The light will be on all the time when the motor is running but thats fine.