If you are going to do the timing belt you might as well go for the water pump too. Especially since it has 180K miles on it. I changed mine when I did the timing belt at 93K miles.

But I would strongly suggest you purchase the water pump from a Kia Dealer to insure you get the right pump. The water pumps for the SOHC and DOHC look nearly identical and will fit each engine. The difference is in the timing belt gear. There have been alot of instances where someone purchased an aftermarket pump and it was the wrong one and chewed up the timing belt. This can be deadly on the SOHC engine because it is an interference engine. So save yourself the potential aggravation and buy it from the dealer and make absolutely certain it's the pump for the SOHC engine. Check http://www.kiausaparts.com for the right part number.