I think the best idea would be to:
[A] Get a Kickstart 3.1 Rom
Order it with the Kickstart 3.1 Floppy disks
[C] Use crossdos to access PC formatted 720k floppy disks with ADF's copied onto them.
The problem really is the limitation of the 720k PC formmated disks .
The other solution would be to use a registered version of 'Amiga Explorer' . Copy the Amiga part onto a PC formatted floppy disk and access it using Crossdos (PC0:) .
Using a NULL MODEM CABLE , you can transfer what you want from PC to Amiga and then use ADF2DISK or something similar to convert the ADF's back to real disk .
Would be much easier if you also had an A600 or A1200 , coz you could use a PCMCIA to CF adapter .