Google for Boston Gear or Small Parts Inc.
Bring cash! Not cheap. Buy direct, and possibly save the markup that
the local dist. puts on it. Likely is that they are buying from Boston
Not exactly hobby shop kind of stuff.
Doesn't Tamiya make worm gear reducer? I could be wrong... I know thay
make a planitary-gear reducer, and that might work for you. It's a kit
and you can stack the planetery gears to adjust the amount of
This is probably not what you're looking for, but if you want to
scrounge for parts, maybe you could scavange one out of an old
If you're interested in *making* a worm-gear drive, I've seen
instructions on how to do it using all-thread and a regular tap. It was
on a telescope making sight. You might try asking around a telescope
making forum, too.
Just some thoughts...