Hi,
I had the exact same software (for Windows) developed for me by someone on Freelancer last year, and I can make it available to you.
It allows to enter the domain names, user name and passwords, and the file list from the local computer, then when you click Start it will upload the file list to each FTP site one by one.
NB: I don't have the source code, only the executable (EXE) file. If you are interested please accept me and I will send it to you as soon as possible.
Bests,
Steve