Work group class laser printers (eg. HP Laserjet 4xxx) are usually very economical. Toner for my printer is €90 from the manufacturer (you can probably get 'refilled' ones cheaper), and is specced for 10k pages. The current cartridge is the smaller capacity one, I think it's rated for 6k pages, and it's currently at 9% capacity with over 9k pages printed (about 2k 'other paper sizes', so these may have been envelopes). I think the lower capacity cartridge was something like €70, so that would be about €0.007 per page (10k pages until the cartridge is empty). It supports postscript, so no driver issues, and even supports Ethernet, so no issues with parallel ports either. It is huge and noisy, however.
The only issue is getting the printer, they are pretty expensive when bought new. Getting them used/surplus locally is the best way, since they are fairly fragile and heavy, so shipping is probably expensive. A long time ago, I bought a much older printer in the same class (Laserjet IID) for something like €100.