The debentures issued therefor may be made payable at such places, within or without Canada, and in such currencies, whether of Canada or some other country, as the Council deems expedient, and if the debentures are, or have been, made payable in lawful money of the United States of America, a dollar so payable shall, for the purpose of such calculation or of any other calculation directed towards ascertaining whether or not any proposed borrowing is within the power of Council, be deemed to be the equivalent of a dollar payable in lawful money of Canada.