Need help with Odometer gear

[MPitt]

I'm working along with the guide at Clark's Garage, as well as a few posts I've found on here from the past, but I have a question concerning the gear for the odometer. Is there any way at all to tell how many teeth it should have other than counting? Mine is completely stripped on the inner part and the outside has disintegrated and started falling apart.

This guide here shows the gear which is the same color as mine (are they all the same color? I don't know), and at the bottom it has a link to buy the 20x21 gear. Clark's says there weren't many 20x22 gears, but doesn't list a reference as to which cars might have had them, so I'm hoping one of our experts here might know.

Thanks

Edit: I just found Speedometergears.com right after posting. They have the 20x22 gear listed under the Km/h gauges. Can anyone confirm this?