If you can get them online, I'll share them using BitTorrent Sync. I could set up sftp server for you, if you need place where to put files. If your upload speed is not great, maybe we can do it differently - I could send you flash card by mail, you write everything to and send it back, and I'll put everything up in BTSync.
Let me know if you want to do this, send me an e-mail to [email protected]
As for those big files - you can easily cut off prestream from latest files. ffmpeg can do that without re-encoding: "ffmpeg -i input.mp4 -c copy -t 00:35:00.0 output.mp4" - that would copy only first 35 minutes. Only you'll need a bit of work here to find the time when prestream ends for each file.