I haven't found any true pricing, most manufactures discount the cameras then hit them with the data retention costs. Here's one example....
http://www.dailynews.com/government-and-politics/20150206/police-body-cameras-are-cheap-compared-to-cost-of-storing-all-that-video
Over 10 years ago when I was a contractor with the county, they asked me to look into digital video recorders for the jail, they were still using tapes at the point. I don't remember the exact timeline, but they had to keep recordings for a certain amount of time, maybe a year, in case of any lawsuits. It all came down to which was going to be cheaper, hot swap hard drives or burning to DVDS, in terms of how much storage would be needed per hour of video.