Thanks guys. My google fu wasn't so strong today. I don't order a lot of maintenance parts online and all the places I was looking at said out of stock.
I ended up ordering the pump online through autozone. I also called my subaru dealer and ordered the o-ring part. My symptoms seem to match what you're desribing in that post, so it's worth a shot for 2 bucks. Hopefully it fixes the problem and I can just take the pump back to autozone.