According to AppleSpec,
http://docs.info.apple.com/article.html?artnum=112209
you have Printer and Modem serial/LocalTalk ports, no parallel, no USB, no Ethernet, and only an LC III PDS slot. You can run 7.1P2 thru 7.6.1.
I'd say a used Apple LaserWriter would be your best bet. If you can find one locally, almost any model in working condition would do the job. If you have to ship it, a lighter model like the LaserWriter 4/600 PS might still be affordable.
A LocalTalk inkjet printer like the StyleWriter or HP DeskWriter might also be a possibility.
New modern printers have incompatible interfaces, require more modern software, and use more computer memory and horsepower than your Mac can provide.
If you are not doing a lot of printing, another possibility is to use a service bureau, like Kinkos print shops, as your printer. You take them a diskette in any of several formats and they print it off for you -- any size, black on white or color.
The LocalTalk interface runs at 240,000 bits/second, much faster than serial.