I believe I've already found a source for cheap, high-capacity battery cells for the CF-01!
Batteryworldcenter.com has a TY-UR18650 lithium ion batteries for $8.68 each. This part number (and picture) seemed very similar to the ones for the cells inside the CF-01 battery pack (apparantly a Panasonic GR18650 or a Sony US18650S according to this website. So I called the Batteryworldcenter.com and asked. He said that he is reasonably sure that the batteries are indeed the same. However, he said that while the older version of this battery (as used in the CF-01) was 1200 aH, these newer ones deliver 1800 aH! This would mean a 50% increase in battery life between charges using these versus the cells included with the CF-01.
Note, these are cells only, not battery packs. You need 3 cells per battery pack. The second link above appears to include instructions (in Japanese) on how to make a battery pack from these cells. Also, the guy at Batteryworldcenter.com told me that he is a battery pack manufacturer and could custom make the battery packs we need, using these cells, if provided with the specs etc. We did not discuss rates. It may or may not be cost effective versus "rolling your own," depending on what he would charge versus the work involved in doing it yourself.
He said he has only a few of these batteries in stock at the moment, but that they are a regular stock item for him and he is expecting 200 more very soon.
Note that I am basing this info strictly on his word and the websites above, and have neither opened up my CF-01 battery pack nor looked at one of batteryworldcenter.com's batteries. But all signs are positive.
I don't have time to work on this issue. Getting everyone their CF-01's is going to take up just about all the time I can spare - at some point I need to get back to work. If someone would like to handle the battery angle sometime in the near future, the guy I spoke to was Leon, and his email address is firstname.lastname@example.org . It might be better for one person to handle this rather than us bombarding the poor guy with a few dozen virtually identical inquiries.