I looked up 68, 71, & 74 on bike bandit. All showed still availabe from Honda.
If you have that weird 6 3/8 sealed beam, www.candlepower.com will have a bolt in H4 headlamp.
you will have to buy the 45/45w H4 bulb separately though.
If it is a 5 3/4 or 7 inch sealed beam there are H4 replacements available.
These will take the 45/45w bulb also.
I can't tell which size the later 450's used from the diagram, just that it looks like a standard sealed beam.
If you have the charging system capacity, those two can be had in 55/65w versions almost anyplace.
Just look for a sealed beam for an older car. The HO ones are best.
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