HP2100A core memory (period) prices

I just received a question from a fellow interested in the pricing of core memory: "How much did this memory cost per bit, byte, or word? I am doing a historical storyboard on the HP2100A used as the data processing system for the HP5930A mass spectrometer and I would like to get some hard data on costs of core memory." Would someone (likely candidates: Jay, Bob :) ) have period price info for a core memory module for the HP2100A? I will pass on responses as well as suggest that he may wish to temporarily join the list to ask other questions about the HP2100A. I will also pass on the email addresses of responders (please indicate if you don't wish me to do so) should he prefer to address questions directly to those more knowledgeable about the HP2100 than I.