I have 2 spare batteries for Sandisk Sansa e2xx - I used to charge them all up before travelling and just swap batts when one died. I don't have a Sansa anymore because I traded it in on the replacement program at Best Buy for an Insignia Pilot (awesome player).
The first person who emails me a mailing address (worldwide, it's not that expensive, I'll pay postage), I'll send them to via USPS postal mail - 2 batts, case screwdriver, packet of case screws. I'm happy to get them to someone who can use them, especially an active RB dev. --Jim (technogeek)