Yes, it is enough, you have to calculate a number of teeth and measure outside and inside diameter. After this, it is possible to get modulus of your teeth. Please look at any machinery handbook for this.
In machinery handbook, under which section? Is there any particular name for it?
in my opinion.
I do not think this piece will take part in a book. this is not an easy task. I think the cost is high. the first method of thinking. a copy of copper. then copper erosion machine. talk to an outsourcing firm. the fastest way.
or a quality steel adhesive.
It appears to be an involute spline.
I don't recommend changing it to metal though.
It's plastic for a reason and I think it's designed to be the failure part since these casement window mechanisms usually have a difficult life with the end users.
The female spline used to be cast into the zinc handle which made repairs more expensive and usually involved some filler material to bridge the stripped out spline...ah, the memories.
If you beef up this part, the next failure most likely will be within the drive housing, which I'm thiking will be a more problematic repair.
I'd order a few plastic replacements and replace when broken again.
An easy repair and a common one with this mechanism.
You might try wrapping 1/64 dia. music wire around the cracked sleeve a couple of times, twist the ends together to tighten like a hose clamp, clip off the ends, then apply a film of high strength epoxy to the spline. Or, if the plastic part can be softened with all purpose pipe cement, use the cement to weld a thin CPVC fitted sleeve to the outside of the broken part. You could also press on a thin steel/aluminum sleeve.