If the miata came with 14" wheels that year, they will probably fit. But if the SE Miata has larger brakes, they might not.
Why can't the original wheels be cleaned sufficiently for the tires to seal? This is not uncommon for alloy wheels, and unless they are badly pitted, they can be cleaned.
If you still need wheels, try ackerWheel.com. They have new, take-off wheels for most cars. My experience with used wheels is that most of them are bent.