I'm reading this board as I'm hoping to be able to afford a low mileage recent Miata....but until then, I have my 14 year old Honda with a lot of miles on it!
A Dealer can install a/c for you. Or if you are mechanically inclined you can get a system from a wrecking yard, install it, and take it to an a/c service place to get it charged. 1994 and newer systems are R-134 refrigerant.
1994 is the first year of the 1.8 motor and the last year of a working factory oil pressure gauge. If you really like your car, at least you know it's history. If you get another you may find unexpected problems.
On the other hand, if you have deferred replacement of the cam belt and service, and your car need tires, brakes, clutch, top, etc, it might be more practical to sell your car and get a car you like with low mileage and less in the way of pending service.
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