There is some really great information on spider mites at this link:
http://nathist.sdstate.edu/orchids/Pests/mites.htm
You may have figured out that I am not a great fan of any of the toxic products, and the pest articles at South Dakota State offer a number of options to replace human deadly chemicals.
I vote no to the repotting - only repot when the plant is happy, the bugs are stressing it out enough. Water well before pest treatment also.