NB is definitely out of your budget unless you are interested in one in my area... $2500 for a 1999 with front end damage. no motor damage, 119k miles. needs a new nose and headlights.
My last Miata was well cared for and ran very well at 179k when it ran into a telephone pole... and even ran well after that. You take care of these engines and they will last forever... however with a 1990-1992, the 1.6L have a problem with the woodruff key wearing a gap between the crankshaft and the timing gear, making your engine retarded... the fix is easy, new key, new timing gear, some liquid metal and the engine is new again. I drove mine very hard and it loved every minute of it... but it was pretty pampered before i got it at 139k...
good luck, if you need any Miata help, I'm seasoned in the world of Miatas.. still have one if you want it. red 1990 with 77k miles.. I would take $3500 if you twisted my arm
