Any sources known for transistors?

[Guest northmn]

Does anyone know of a source for these (GM-specific value)transistors that are in all the modules .It seems the transistor is always the problem in module failure.Mainline transistors close to these values produce nothing but problematic outcomes.I'am lookimg for a #7594M152 EBC transistor for the engine light driver right now.The module will costs me $75.00 from dealer-still available if that's the way I've gota go.