where can i get a custom spur gear?

[suicideneil]

Depends, if you are just after a fairly normal type gear, like an oversized pinion that attaches to a shaft via a setscrew, then you can go to their online catalogue and just fill in the fields on the order form:

https://sdp-si.com/eStore/

Gears > spur gears > metal. You can select the pitch (adjust metric or imperial before you start), tooth count, material, hub style, etc etc (might be worth asking the guys that have used the site before about some of the weirder options like pitch diameter and pressure angle).

If you are after something different that requires a special 3D machining process to make, then you can ask for a quote:

http://sdp-si.com/web/html/rfq.htm

with the option to include drawings or specs etc.

[Ryu James]

nice Neil! that helps a ton. should get me going in the right direction anyway. i will be sure to post progress.