The only modifications I made was to plastic tabs on the case of the ballast and some plastic inside the head of the light. The ballast is sealed so the actual ballast was not modified at all. The wire stripper and wire nuts were just used to connect the wires. There is nothing special about an Ott ballast, it is the bulb color that sets them apart from other lamps.
As for Ott selling replacement ballasts the website says that they now offer replacement parts but they didn't have them in stock for this light. The person who helped me just offered to sell me a new one very cheap, like 25% of the MSRP. I got the impression that they do not have parts available and he was just to keep me from having a negative opinion of their products. No price was discussed because he stated that they "May have the parts available in early to late summer"