Here's what I know about DigiBeta:
A major source of trouble was the slip ring assembly. You had to clean it periodically and afterward run an auto setup. You played an alignment tape and it did the setups automatically. If it passed, you cursored down to save to NVRAM and then exit. If it didn't pass most likely you need a new slip ring assembly.
The DigiBetas are 10 Bit Discrete Cosine Transform and they SX's are 8 bit MPEG so they are not interchangeable.
Digibeta is a production format and SX is an ENG format. Both decks will play analog tapes. At one time we had THREE formats in each of our eight edit rooms. That was after the new company bought us and decided to go DVC Pro. The news photogs liked the SX cameras the best. It was the most robust. The DVC Pro seemed to be the flimsiest and gave a lot of trouble. But the cameras were cheaper. A DVCPro camera with lens was about $17K. And Panasonic was giving a special deal to CBS stations who bought them.
A possible source of parts is AheadTek:
http://www.aheadtek.com/