Fujitsu are not known to have the best battery capacity, and I have seen different battery models on the exact same Amilo model, so you have to be very careful you get the right battery. Some models come in 6600mah, you just have to search your battery number, and preferably confirm by picture and specs. I have bought new battery for Fujitsu, that fit in the slot, had identical specs, yet did not work. Fujitsu are fuzzy that way. In the battery there is some kind of chip that need to identified and read by the computer, and not all brands are flexible to read this card.
Yes other models have the same bezel, but I am afraid I cannot help with numbers. However, you are very likely to find parts on ebay, and on the web in general.
I have an old laptop with a nearly flat battery, and I am thinking of replacing the battery cells my self, if I can find a way to open the casing
