Does anyone have meaningful input on this?

Hello.

I am looking for some info about the infamous idler gears for my EMD F9 fleet. I don't want to junk the locos since they were my fathers and I want to keep them as-is and replace the cracked gear. I have a friend with a 3D printer who said he would make a few for me.

I believe these gears are not made by Bachmann and no substitutes or replacements are available, correct? Here is what I gathered from one of the cracked gears..

It is a double gear.. Large gear is 18 tooth approx 10mm diameter. Smaller gear is 8 tooth approx 4mm in diameter. The center hole is approx 2mm in diameter.

Does this seem right? I also have no idea what pitch or modulus they are.. Are there 3D printer files out there already to make this gear or does it have to be designed from scratch?

NWSL makes a gear close to this, but I haven't found anyone to confirm.. It is p/n 2228-6



Disclaimer:
I know these pancake motors are junk and so are the gear boxes. They are 3 pole, noisy, hard to control, etc... My goal is to revive my dad's loco without repowering it or buying other locos for parts..




Thanks.