Unrelated to the "Linux-friendly, non-abusive" matter (which other members here will no doubt deal with), my immediate thought is, it CANNOT be an inkjet device. With your infrequent printing schedule, such a device would give you endless troubles and expenses with dried-out, often unresurrectable, inkjet cartridges or nozzles. If colour is not needed, then it should be a laser device. Those are fine with infrequent printing, though with such low print volumes, you'd still have the issue that even toner does deteriorate after a few years of sitting in a cartridge.
Back to inkjet devices: You could print a handful of useless "maintenance" pages every 5 days or so to keep the cartridges and nozzles in good condition, which would result in way more
"maintenance" pages than real pages being printed over time, with a much higher cost per real page than normal.
The dot-matrix printers of the distant past didn't have the above issues. :) :)
Hartmut W Sager - Tel +1-204-339-8331