Is it okay to get the varicella vaccine around the time I'm getting a root canal treatment? worried..?

The CDC's website does not give any information on this - I'd ask your doctor before you go in for your scheduled vaccine. The doctor is your best bet for such information, people on this site don't necessarily have the qualifications to answer your question.

Definately not a good idea.
The reason why I am saying this is because if you have a reaction you will not be able to tell what caused the problem. Also, a vaccine (which I NEVER recommend to anyone) will bring your immune system down as does a root canal as it stresses a body. In addition, you can have an allergic reaction to the Vaccine as well as the Root Canal products (Gutta Percha) and you will not be able to distinguish which you are reacting to as both can be systemic.

Over time, Root canals end up being rotted roots left in your mouth which can often cause low level infections and a host of immunological and chronic illnesses.