BenMash

Hi, everyone. Posting this again in case someone who might be able to assist missed it. I need a Shimano Ultegra Di2 RD-6770 10-speed rear derailleur. Very scarce to find one. If you know of anyone is selling please let me know, second part of my question is. Can I possible change the derailleur to a 11 speed alone or do I need to get a entire kit.

Hi everyone, I am wondering if anyone can assist me. I am new to cycling, and I bought a pre-owned bike. I only cycled for a month, and my derailleur is broken. Is anyone selling a 10-speed Shimano Ultegra Di2 derailleur? I know these are hard to find. Regards