All MIDI attachments must be one of the following:
Your own, original work submitted under some license that permits free private use (I recommend public domain or Creative Commons).
Adapted from works created prior to 1923. This goes for both the composition and arrangement. This means you cannot post MIDI versions of recent songs.
Most likely you need 10 fingers and 2 feet to play that plus an organ console that includes a pedalboard. Actually you can get away with one foot as organs have a way to play a note plus the octave with one key.