I went through the same issue about 5 years ago with my 2005 Tucson re: the P.S. fluid change. Even back then Hyundai did not sell any P.S. fluid; however, KIA in Canada did, and so I had them do a complete flush and one more since. And I bought a small bottle of KAI fluid to use in the future.
However, today, the 9th of Sept. 2016, I have a slow P.S. fluid leak and will need to top it off or do a complete change. I'm contemplating on using the Valvoline MaxLife P.S. Fluid, which is clear in color but the label does not say if it's okay to use in Hyundais (just says some import vehicles).
So I called Niteo (1-844-696-4836) which bought out the MaxLife oils from Valvoline (
http://www.niteoproducts.com/). Even the tech said he couldn't be sure if this MaxLife P.S. fluid is okay to use. I suspect Hyundai and Kia would not confirm or deny to Valvoline at the time that this MaxLife oil is compatible with their vehicles.
I'm going to go with what "rooflessVW" said about hydraulic oils being the same and top up my P.S. reservoir with the MaxLife stuff. (BTW: Valvoline MaxLife High Mileage DEX/Merc ATF works very well in my transmission, for which I used the Hyundai SP-III exclusively since I bought the vehicle. I just did a drain and refill about 8,000 km or 5,000 miles ago, and no problems.)