If you have the stock stereo deck, you could get a tape adapter and this. It has a built in mic as well.

This is the one I got

I've had one if these for a year and I love it. I decided I'd rather have the wireless version but instead of purchasing a second one, I added a Bluetooth receiver for $16 and converted it to wireless myself. I just trimmed the wires to about 6 inches, soldered a new jack in place, and tucked the receiver inside the headband.

Here's the link to the receiver I used:

http://www.amazon.com/gp/aw/d/B008AGQMQC

Hmm. Thats tricky. None of the high quality/power FM transmitters have bluetooth. Maybe one of these plugged into the line in? https://www.amazon.com/Mpow-Bluetooth-Receiver-Streaming-Hands-free/dp/B008AGQMQC