Several decades ago I seem to recall L.L. Bean making their Maine Guide Pack Boot with an optional sole, that being similar to one having large diameter rubber hobnails rather than lugs or what I describe as their "chain mail" sole pattern. Bean claimed the rubber hobnails furnished excellent traction, especially in snow and gumbo-type mud, without picking up snow or mud that would cause the boot to become very heavy and clumsy. . . . At least this is what I think I remember.

Several times when hunting, I have had to cross shallow streams or brooks. My boots were, and are, about six-inch uppers; the water is always 8-10 inches deep. Include hunting in two feet of snow and the Bean boot lug pattern that I think I remember becomes rather attractive.

Bean's web site does not show their pack boot as being available with such a sole. Has anyone noticed this sort of bobbed sole as being available in an insulated pack boot?

You're looking for "airbob" soles. Schnees used them for quite a while then changed to a modified version. Still work good, maybe better than the original.

http://www.schnees.com/product/SCHNEES-Guide-ADV/Schnees-Pac-Boots

Bean called then Bean-Bob. I have a pair of insulated gore-Tex Maine hunting boots that came that way. Best pair of boots i have ever owned, but unfortunately they no longer offer the sole in anything but pack boots. I had my pair resoled and had to use the chain thread bottom.
The Schnee boots look similar but are a much heavier boot. Good quality but are they now made offshore now?

Not traditional Pac boot style but these are available with the soles that look like what you described, are insulated for cold weather use, waterproof, and a well known reputable brand name.

http://www.lacrossefootwear.com/catalog/product/view/id/212/

Air bob

L Tread

Danner Elk Hunter

A thread on this subject from a couple of years back.

http://www.24hourcampfire.com/ubbthreads/ubbthreads.php/topics/8564725/all/Pac_boot_sole

Those Air Bobs are okay In mud, soft ground, or soft snow but on wet rocks or wet wood porch steps, truck running boards they run a close second to ball bearings.

Sorrels. I have a pair and they work great dry or wet.

I hunted Idaho elk last year in the Schnee pacs with air bob soles. There was 10" of fresh snow on top of blown down tree branches. Traction while on snow/ mt sides was excellent and the boots were not too heavy for mt. hiking. But boy, did they slide on the down limbs!

The only thing that grips wet limbs is sharp steel.

Grip tight boots are good