There's a reason for that. 17x9 cast is what was produced specifically by YearOne for the models that these rims were found on. Any other model will be rarely seen unless you go looking for it.
There was also a 2-piece dish and centre, only limited production and no longer available when last looked. It came in larger sizes and feature custom offset and stud patterns to order. There's a few others that offer short runs but often seems like they have booked the production slot of the same basic rims.
Although that pic looks cast and at least 18". Some guys like RAMC were doing that one, but very little offered for 3rd or 4th gens.
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