That was easy! Nice finds, incidentally. The first link you provided is a clone of the Motorola folding-plug telephone charger, with a standard USB socket that the SanDisk Fuze cable will plug into.
This is the type of wee beastie that you want. Essentially, if it has a standard USB socket, it’s hard to go wrong, with one exception: if the Fuze says “connected” while plugged into the wall charger, there’s a connection to the data pins within the charger (some MP3 players need this, but the Sansa does not).
The two other chargers shown have what looks like a mini-B USB connector, usable for Sansa Clip.
Further, avoid aftermarket chargers with the 30-pin device connector that do not specifically state that it’s a SanDisk Sansa compatible cable, as there are many iPod chargers that offer a 30-pin end connector that looks similar to the SanDisk one, but they will FRY the Sansa. Ipod connections are different from the Sansa ones.