Tons of restaurants, chains and local, will give you big take-out versions of several of their dishes at a lower per-serving price than they'd normally be. Same thing a company might do to cater lunch for a largish team or smallish business unit. The smart ones will throw in a freebee or two just to make you feel good and want to place a big-ass order with them again in the future. Usually they just need to know a day in advance or something. Pick it up, put it on the table, plates and silverware next to the tubs o' food. Done. Get a shortlist of places your social circle'd like that aren't too far away and call them, probably a few of them are happy to do that (they're a business, after all, and you're offering to give them money for The Thing They Do).