Our favourites are from Salty Dog Canvas and Z-Control.
Salty Dog just makes some really good quality, durable options. I like the tugs with sheep shearling. I also used to get toys all the time from them because I lived about a half hour down the road from them and didn't have to pay for shipping.
Z-Control has some really awesome real fur options. I bought a raccoon fur water bottle tug for Kili for demos. She normally isn't allowed toys with real fur, but I wanted something extra special and doggy crack like for the high arousal atmosphere of demos. We'll see how well it works at our first show, but the one or two times I showed it to her at home she went absolutely bonkers.