Look into an office supply / overstock / reseller store around you. When businesses close up shop, they usually sell their desks, chairs, etc. to some kind of overstock store. You can usually go there and get very nice chairs for less then 1/4 of the normal cost
For you, I suggest sticking to Discord. I am of the mind that your effort should be focused on your community instead of enforcing a FOSS philosophy upon a group that may not have any interest in doing so.
If you are creating a new community, this is a different conversation, of course.