You'll have an interesting experiment on your hands with a 3D printed fan as presented in the images. If printed horizontally, which is optimum, the individual vanes will have fairly narrow layers. This orientation is the weakest for such a design, but there's no real practical work-around for most hobbyist printers.

That fan design may print well and be strong enough in SLS (nylon) but that could cost more than the aftermarket item and would require a third party service.

I'm willing to give a shot at building the model.

Can you provide better photographs than those shown in the link? They are very poor from a reverse engineering standpoint.

Outside diameter, hub diameter, lobe diameter, lobe offset, vane thickness, vane height, vane edge inside diameter, vane edge outside diameter, thickness at points of change as well as diameter of the thickness changes.
Unusual features such as pins or holes? It appears there are pins on the underside, but it's difficult to determine. If there are pins, precise location reference is needed, including diameter of pins or holes, location (angular displacement, diameter of reference circle) and any other useful information.

Overall it's not a particular difficult item to design (I hope) but the printing part will be more of a test or experiment, I believe. I have the ability to print FFF in nylon, now that I have a high-temperature capable printer, so it may not be completely hopeless.