A yard of broad cloth would run you two beavers, and a gallon of rum four. One blanket was six beavers, and a pair of cargo breeches three. It seems like a luxury, but two ivory combs were just one beaver.
This system was put in place by the Hudson Bay Company and it radically disrupted the economic world for Indigenous tribes throughout the area, leading to the "Beaver Wars" and upending traditional cultural systems and practices.
The trade goods were a powerful incentive, and the impact on the beaver population can be seen by the annual harvest recorded by the Hudson Bay company in the same report.
To take a look yourself, ask for John Strange 1749 Report from the Committee, Appointed to Enquire into the State and Condition of the Countries Adjoining to Hudson’s Bay, and of the Trade Carried on There : Together with an Appendix (Stefansson F1060.4 .G774 1749).