I bought a reman converter. The tool is expensive, but the bearing is cheap($1 or so). If you can figure out how to pull it out without damaging the bore or dropping stuff into the converter, you could do it yourself. You may want to ask local shops how they do it, and how much they charge just to change the bearing if you bring in the converter.
At 67000 you could go either way(rebuild or just fix leak). Based on my experience I would install the 2 upgrade kits(Trans-go and Superior) but might skip a full rebuild at that mileage. The cost difference is minimal, but the time is significant. You still need to crack open the case to do the lube modifications. If you don't already have one, install an auxiliary cooler. If you have damage to the outside of the converter sealing surface, get another converter. I got mine for $80 incl shipping on ebay. I'm glad I did the full rebuild for peace of mind. Many of the rubber seals were soft, and the main pressure regulator in the valve body was worn. The result is a very nice shifting transmission.