Depending on the electret microphone you use, you might have to tweek R4 to set the gain of the pre-amplifier. Depending on the Q of the LC-part (usually not very good when using off-the-shelf SMD parts) you may also have to re-bias the end stage of the circuit. For the coil you can use a ECM45T Series Inductor.

You can download the PCB design here (only 2.5Kb). It's a double-sided PCB in CorelDraw 3.0 format (zip compressed).