The Miata uses high ohm injectors (saturated type, 12-16 ohms) and has a fairly unique rounded injector connector. The 205cc 1.6 injectors can be directly replaced with the 94-97 230cc 1.8 units. Many other makes injectors are also a direct fit, including the late 87-89
Toyota injector from the normally aspirated MR2 (4AGE) 1.6 DOHC at 213cc (Beige top), 89-91 B2200 truck at 224cc, 89.5-92 Toyota Supra non turbo at 305cc (light green top) and turbo 430cc (black top), 89-91 B2600 truck at 326cc and the 89-92 Mazda RX-7 non turbo at 440cc. Most OEM injectors of ealier vintage or larger capacilty either have a different shaped connector requiring swapping the pins to the Miata connector or soldering a new connector on. Examples of this are the 88-89 323 GTX/91-95 Capri Xr2/88-92 MX6 2.2 turbo 300cc injectors. Many larger aftermarket and some OEM injectors like the 86-88 RX-7 440cc are of the low ohm variety (Peak and Hold type, 2-6 ohms) which requires a balast resister in line to work with the factory ECU injector drivers. FYI, if you are running at 150 rwhp or over then the factory 94-97 1.8 230cc injectors are at full duty cycle.
