I live in the area and have bowhunted it for close to 30 years and have only seen Mulies in the summer. Seems like by hunting season comes they move although I haven't hunted the area west of lead towards Buckhorn. Even last year when bowhunting elk on the very west end of Lawrence Co in September, I never ran into any mulies. Certainly some large bucks available.
there are definitely some quality mule deer in the area if you can locate them but the population has been on the down hill for awhile so they can be pretty tough to find. They used to hang out pretty close to Lead, even right around the houses a lot of the time. Plenty of whitetails around if you want to chase them though, Personally i like to stand hunt the whitetails but you could have luck either way.