I will need to check the stamps on the wheel to see exactly what they are. Had a look today to check what width they are and that they are all the same ... which they are.
I'm not really interested in buying new wheels so its either use the 17s or the 15s. At least the 17s would be a change and would probably look better on the car without deviating too much from Toyota's original 'vision'.
One of the guys on OC said he thought these might be an ET40 wheel. Not sure if this is something you can tell from a pic but .....
I think I will put one of hte wheels on the rear of the car in near future to see how it looks. They currently have tyres but some of them are about 5000 miles beyond legal - I kid you not

there is steel showing on one.