I guess that's to prevent hobbyists from collaborating with professionals.
I found the
igs from which I made the SLDPRT... don't know where I got it originally.
Here's a link where you can find various sizes to download from 3DContentCentral. You have to log in there. The models there are OK but less fidelity than the igs on my google Drive. L means lubricated and - means not lubricated so no difference in the CAD model.
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