[Darkover]

I always think: there should be a software that if you connect a camera and scan (take a panoramic video) the objectives, you can get the 3-D models automatically.

There are scanner like this. But it is more complicate than you believe.

Your gear is perhaps a standard part. So someone with experience in 3D-software like autocad can draw it in a minute. But a gear should fit very good and perhaps if you print it, it needs to be a little bit smaler or bigger. If you had a 3D-printer in your workshop you would print it three times with different sizes until the tooth fit perfectly.
The next problem. There is a reason why this gear fail so often. I think Pentax calculate something wrong and there is to much pressure in the middle. So perhaps you need the hole a little bit bigger. A very little bit.

Olaf

[grahame]

I contacted a friend in Japan and asked if he could get the gear from the store. Mailing a camera back and forth cost quite a lot. And I know I can fix it if I have the part.
If he can buy one, I will post here to see in case anyone else need it.

[Not a Number]

Any machine shop capable of cutting small gears will cut you one. All you need is the outside diameter, diameter of the opening, thickness and number of teeth. Given those parameters the company in Poland linked above may have them in-stock or will cut them for you.

[dcpropilot]

I purchased the brass spur gear from a place in Europe and replaced it myself. Worked fine! I ordered a few to have on hand, and may have some spares.

[felixkh]

Thank you for the information. Do you know how much did they charge for the repair?

His repair was 30,000 yen, not inclusive of shipping.