I'm pretty sure those are proprietary motorola.
I don't think they would work, and besides you don't want them.
They need to use the USB port because someone seems to have forgotten to make a stereo headset jack on the original RAZR design, even though they advertise it as supporting MP3 playback now.
Rather than go through the trouble of re-designing their now infamous handset, moto decided to keep the body and external ports of the RAZR as is, and found a workaround but using the USB port to send audio in stereo.
The result? If you own a RAZR and want to listen to music on it, you have to use this GROSSLY OVERPRICED (for what it is) headset.
So, basically, even if it DID work, I wouldn't recommend dropping $30 on it. Maybe if they were high quality from some fancy audiophile brand name, but not Motorola. A stereo headset should cost $10-$20, with off brand cheap-o ones starting around $5, if they're a standard type (2.5mm is actually considered a standard size).
Nowadays, there are tons of phones that play stereo through the 2.5mm plug, so if you look around you shouldn't have too much trouble finding one that fits your needs.