Your pyrethrin you commented about on your first post will work.
Also that exact ivermectin I posted on the link should be at tractor supply or a local feed store. Its the cheapest and it works.
We had a mite discussion the other day, all this will apply for leg mites too. But you can continue soaking legs and vaseline if you'd like as well as whats recommended in this thread. Read through it all and if you have any more questions, ask away. The dosage will be the exact same for leg...