27/28/29 EPROMs
You didn't mention whether you already had a UV chip eraser, it's an additional expense needed for using windowed EPROMs. Windowed ceramic EPROMs are much more expensive to manufacture than plastic flash EPROMs. There are lots of ceramic EPROMs on the surplus market, that's why they're so cheap nowadays. That said, there's nothing wrong with putting 27xxx parts to use in hobbyist projects. It's just more convenient to use flash EPROMs, they are easier to update. Windowed EPROMs usually last for a few hundred program/erase cycles, Flash EPROMs are good for at least 10K, while most EEPROMs today are guaranteed for at least 100K cycles.
I like the 29Fxxx parts, they're inexpensive and only require +5V for programming (as opposed to the 28Fxxx family, which needs +12V). The "5V only" requirement simplifies things if you want to do in-circuit reprogramming. In the U.S., Jameco sells 29F010s for less than the cost of many 27xxx parts.
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Although the 29Fxxx series originally came from AMD, you may want to use the Atmel datasheet: