The only thing cheaper than what you see in the aftermarket is buy a period correct, or new, under dash hang down evaporator and buy the under hood components and have it plumbed and filled.
Amazon has an under dash similar to old school for $150. Speedway $229.
Amazon has a complete under dash kit for $510.
For those on a budget, go with under dash rather than the thin line "built in" look. The center passenger has limited leg room however.

Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn