One of my correspondents has a batch of new gears available, made of Delrin, a
durable plastic robust enough that it is commonly used to replace metal.
He is offering them for $15 + $5 shipping to anywhere in the world.
If you're interested, send him
email.
The CBA bulb is tubular with ceramic endcaps and a metal base.
The ELH and ENH have a faceted integral reflector,
and either type of bulb may be used.
An ELH bulb is brighter and cheaper; an ENH bulb lasts longer but is more
expensive and produces less light.
Any well-stocked photo store should have these bulbs available.
Online sources: