So I found a Lombard on eBay.
I've been interested in a dev system with Grackle+Paddington for a while, so when one showed up on ebay listed as parts or not working, with a broken hinge; a column of dead pixels on the screen; and powering on but not booting, I ended up submitting an offer of £40 which was accepted.
When it arrived, I got it booting into OSX easily enough (someone blessed the OS9 system folder, but OSX was still installed, so I booted into OSX through OF then blessed the OSX system folder).
Once booted I had a nice surprise. The eBay seller couldn't boot the system so listed it under the stock specs on the sticker on the bottom. Turns out it had been upgraded heavily. I was expecting G3 at 333MHz, 64MB of RAM and 4GB HD, I got G3 at 400MHz, the full 512MB of RAM and 20GB HD (I noticed the HD has an apple sticker on it so I guess it came out of some other mac?). Full of the previous owner's personal data of course.
(One of the first things I did was figure out how to reset nvram in hardware. After figuring that out I tried enabling OF little endian mode, because theoretically that should work on grackle systems. Unfortunately it didn't work, either there's a bug in the endianness switching code, or some other part of OF failed to initialise. For anyone else interested, resetting OF nvram on a lombard can be done with the PMU reset button.)
