I have been soloing these wolves for 4 lvls now and have not seen a single belt drop. When you figure that in 4 lvls I must have killed maybe 80-100 of these suckas, the belt must be rare. I have had 3 of those steel collars drop but no spikey one yet.
Its Pretty Rare. I have been Hunting Wolves and Giants for quite a while for faction and about every 40th wolf will have one. Now that is a ruff estimate at best but it is rare. Your are quite lucky to have 2 drop so fast