Are you just interested in bulbs? or are you open to a LED light bar or Led pod's? i have several different size light bars on 3 different machines. A 6 inch light bar mounted on the bumper or handle bars can give off more light than a new vehicles head lights. i have had great luck with Black Oak brand LEDs. they sell bars and light pods at reasonable prices and are a family/veteran owned company in Florida.
if you purchase a set of led's, stay away from the fan cooled. I bought a set and after the first ride the fans plugged with dirt and stopped spinning. There are non fan cooled options, and the led's are a far superior light. IMHO.