Great news. At least they didn't knick you for a new or rebuilt HPOP which is often done by dealers as it takes fewer labor hours but they can pocket some nice coin on a parts sale. The HPOP (High Pressure Oil Pump)on the 7.3 PSD is chock full of O-rings. The HPOP actuates the fuel injectors and can operate at 3000psi at WOT so the O-rings have a big job to do. Having replaced all the O-rings on my '02 7.3 HPOP it is no picnic. You pretty much spend a day laying face down over the top of the radiator digging around all manner of knuckle busters in the valley. More time consuming than anything but well within a decent shade tree mechanic's abilities. I had a great experience with dieselorings.com as I spent less than $100 for all the O-rings and seals to do the job and they have very good, well illustrated instructions. I still buy fuel filters and other stuff from them and it has saved me $1000's that otherwise would have gone to a dealer.