That is ridiculous. Getting a converter stalled is at most a 6-800.00 job.
What stall do you want. How high of rpm. I have an old one from when I had a 722.3 that is around 2200rpm if I remember. It has been a long time since it was in a car so I honestly do not remember the number. Shipping would be quite a bit but I would sell it for 400.00. But I would suggest calling around to see if you can find someone local that does this kind of work on other cars and have them do this for yours. Converters are all pretty much the same concept.