Why not be brave and make your own.
Electret insert, with voltage feed and conditioning circuit ( several circuits and advice on the web) containing one capacitor and 2 resistors, bit of twin - screened mike cable, small plastic box and ptt switch.All available from Maplin and other suppliers.
Make it up into a tie clip mike with a small bulldog clip and small plastic tube. Then experience the satisfaction following the great reports from your < £5 investment. If it is a stereo mike jack it should be able to provide the 5V for the electret, if not, consider fitting a 3V lithium battery in the ptt box with an on - off switch.
Ingenuity rules OK.