Ended up breaking one of the buttons somehow. I see only two listed on eBay with no option for "buy it now" and I didn't see anything on Apex Auto Parts (will contact them later today). Just wondering if anyone had one for a S5 lying around as I'd like this fixed ASAP.
On a side note, the one I just broke had an auto up/down feature for the driver's window - not something I have seen on any that are/were for sale. Also for some reason the buttons are backwards (ie left controls passenger's window and right controls driver's). Do I have some weird JDM switch? Just curious; I don't care about the auto up/down feature; just looking for a new switch!