Lee Valley (leevalley.com or 800-267-8767) has them. Their stuff is high quality. It's kind of expensive (The title of their catalogue-- Lee Valley Fine Woodworking Tools-- should be a warning) but in my experience it's usually worth the cost.
Another place to try is Cutters' Choice (888-817-4707). I don't have their full catalogue, but I know they sell a lot of cutting and climbing equipment, so they may have what you need, and their prices are reasonable.
My experience won't help you much. One of my pickaroons came from an antique tool swap meet. The other came from a yard sale in Timmins ON (Yard sales , or the local hardware store, might be something to try if you live in an area where forestry is a major industry) My tongs came from Princess Auto, but that was a long time ago, and I haven't seen any forestry tools there lately.