The hardware in my Epson isn't all "stock." As they system
came with expansion slots, it has been "expanded" to
include the best available hardware that is compatible
with this old of a system. I personally feel that upgrades
are entire inline with a retro system; when it was new, the
owner would have upgraded everything they could have with
what was available during the life of the machine.

My Equity I+ was manufacturered in 1989. I have an 8-bit IDE
card in it that was manufactured in 1994 (ADP-50L). The video
card was manufactured in 1989, but is an 8/16-bit style,
jumper makes it work in either configuration (Oaktech-37)
The ethernet card is a 3c503, not sure on manf. date, but the
driver is from 1989. The floppy drive is original to the
machine. I also have a modern IDE-to-CF adapter, and a
modern CF card. CF came to market in 1994, so I feel like
it's still in the range, plus it works flawlessly with all
of the old hardware, CF being electrically identical to IDE.