A 7 degree stem is not the same as a 17 degree stem.

A 7 degree stem can be + or - 7 degrees from the headtube angle.

A 17 degree stem can be + or - 17 degrees from the headtube angle.

I wouldn't recommend buying a stem just to achieve a "look." I'd recommend a stem that suits your fit and flexibility.

I also wouldn't recommend buying a $25 "carbon" stem on Ebay.