The answer is no, I fear.

And here's why I think so...

The floppy in a PA80 is "PC Compatible". What you (and indeed a lot of us out here with PC compatible drives on our keyboards) need is a higher capacity device that has a standard PC floppy interface AND (this is the tricky bit) fools the keyboard into believing it is still a normal floppy disc. The higher-capacity devices on PCs such as the LS120 offer "normal" floppy compatability using the standard interface; the higher capacity mode of operation requires custom drivers to be loaded onto the PC to enable the extra capacity. This is not possible with a keyboard unless the manufacturer explictly upgrades the operating system to include support for the device; this hasn't happened so far to my knowledge.