Circle track safety team leader here.
Look into the Motorola CP 150 and/or 200. They should be narrowband compliant, are relatively inexpensive, and should be easy to program, assuming you have the right software and cable.
And, your two pin Motorola cords will work with them. Failing that, check to see if the cords are removable from the headset. If you decide to go with Kenwoods, then you just need to replace the cord.
Personally, I use either an HT-1000 or an HT-750. Both use an audio adapter on the radio, the HT-1000 is a one pin cord, while the HT-750 uses the standard Moto two pin cord.
Edit: Personally, I'd stay away from the Chinese handhelds out there. If your staff was using SP-50s, then these will be way more radio than they need. There is also the durability factor to consider; my Motos have taken many a bounce off the track and survived. With these, not so much.
Last edited by KB8QDM; 03-13-2013 at 11:43 PM..