HELP! Vintage Overlock/Serger parts

I recently acquired a Bernette 43D (Bernina) serger. The motor and light both work, but I can't test the functionality because the entire thread reel stand/reel bar assembly is missing. Bernina's site doesn't offer any support for a machine so old, and I've hit a wall trying to find replacement parts (other than a foot control, which I have) online. (NOTE: It is entirely possible that I may need even more parts, but I've never used a serger before and therefore don't know what to look for. I have NONE of the accessories listed in the manual, but they seem extraneous.)

Do any of you dear readers have a source, suggestions, or a familiarity with this particular machine? Is it even worth my time to try to track down the missing parts?

Thanks for any help you can offer!