I use the Hella stuff since 32 years. Here in Germany we have to kick out the sealed beam stuff and change to European lightning. So you have to look for a legal replacement, which you will find over here easily for the SAE 2 headlight or 4 headlight system. It is simply a mass production part. With H4 the light is really great. The seal beam stuff is compared with that like a tea light. the replacements over here are relatively cheep, some 30 Euro per headlight. Bulbs extra.
Wolf