The best treatment and one that I recently used is ivermectin paste (horse paste wormer, 1.87%). I just went to my local feed store and bought the smallest tube I could get (cost about $7). You feed one rice grain sized bit of paste for every 4 pounds of body weight. I gave my 6 month old large breed does one green pea sized bit. My 9 week old buck I fed one rice sized bit.
To feed the past I used a baby spoon and smeared it over their upper lip (or as close to their mouth as I could get, not an easy task but the spoon helped a lot). They immediately start lilcking and cleaning the paste off their face with their paws, in that action they injested all of the medicine.
I will treat twice more, every 10-14 days. This should kill the mites and take care of the eggs that will hatch in the mean time. All of your rabbits need to be treated whether they show mites or not.