Wow, $200 for an oil pump on a 2.3L is a bit out there. Check
www.rockauto.com and see what you think then, I think they are around $70. The oil seal on the shaft is not too hard to replace, but it can take some time if you are not familiar with pulling and replacing seals. The seal and gasket kit is usually around $5-6 though.
I managed to find a nice new Melling pump on ebay when I did the timing belt on my 2.3L for less than $30 shipped, so I skipped redoing the seal. I was really time constrained for doing the belt so I bought everything in advance by a ways. I had less than one day and it had to drive me 70 miles home at the end of it then to work the next day. I've since done two more of them and still have yet to use the tensioner pulley I bought. All of them I've replaced the water pump, but only did the oil pump on the first truck I worked on.