If it has all the right operating system bits installed, the 610 will also quite happily read/write to a previously PC-formatted floppy.
50 pin drives are still commonly and inexpensively available on ebay up to about 4.5GB in size, less commonly to about 9GB. If you want bigger you'll need an adapter. There are a few sellers around who would be able to sell you both the drive and adapter together, sometimes tested together and ready to go into a Mac (although they charge a premium to do so).
If your main use will be word processing, I would think anywhere between 1GB and 4.5GB should be plenty, especially once you've got network access.
Beware the taller, older Seagate Barracudas - they sound like an angle grinder colliding with a working jet engine.
50 pin drives are still commonly and inexpensively available on ebay up to about 4.5GB in size, less commonly to about 9GB. If you want bigger you'll need an adapter. There are a few sellers around who would be able to sell you both the drive and adapter together, sometimes tested together and ready to go into a Mac (although they charge a premium to do so).
If your main use will be word processing, I would think anywhere between 1GB and 4.5GB should be plenty, especially once you've got network access.
Beware the taller, older Seagate Barracudas - they sound like an angle grinder colliding with a working jet engine.