Up for your consideration is this pair of Stromberg-Carlson model TM-1010 input transformers. These are a high quality transformers with Amphenol 9-pin miniature bases.
Stromberg-Carlson
Model TM-1010
Microphone Input Transformer
Input Impedance: 150 ohms
Output Impedance: 600 ohms
Frequency Response: 30-20,000 cycles
Shielding: Magnetic and electrostatic
Basing: 9-Pin miniature