Thanks for all the insight. There's so much expertise on this list!

Thanks to a combination of the information and links in this thread, and a
little research of my own, it turns out its very easy to make a long null
modem cable using 2 cisco DB9-RJ45 console cables and a straight-through
cat5/6 cable.

Eventually I figured out it's as simple as cutting the RJ45 connector off
one of the cisco cables and crimping on a new RJ45 end backwards, i.e.,
grey-blue-green-yellow-orange-red-brown-black, instead of the reverse. Plug
this "rolled" console cable and a standard console cable into opposite ends
of a straight-through ethernet cable and you have a null modem. Working at
~15m here.

Thanks again to the folks on this list for the inspiration and information
to get this done.

db