US Forest Service doen't advertise the PMA's, but they do have a map booklet (I called USFS at Duluth, last spring, and they graciously sent the info) very useful for picking out PMA and zone within that; the maps are not highly detailed, but give you enough to draw in the boundaries on your trip map(s).  My buddy and I had entry via Hog Creek and did a loop to come out at Kawishiwi.  We reserved a PMA site for one lake along the way; reserved at Tofte, where we picked up the BWCA permit.  It was worth a bit of extra effort (followed a grown-over portage, although, in theory, they don't want you to use traces of trails or campsites but rather to " leave no trace..".).  There are some pretty gems back in those places, and maybe best when they are on the way to no where else...   Ripple