Comprenew again has a stock of new monitors, right now they have Iiyama, Mitsubishi, and Nokia 21 inchers for $299 or less. Keep in mind that these are used, but usually in fine condition. I got an Intergraph from them 6 months ago and was pleased.
https://www.comprenew.com/cgi-local/compreshop.cgi?action=show&type=20_and_up_monitors
https://www.comprenew.com/cgi-local/compreshop.cgi?action=show&type=20_and_up_monitors