You say "speaker part", are you referring to a shoulder speaker mic or the actual speaker in a radio??? If you are referring to the shoulder mic, what model speaker mic do you have? If you have the higher end model, (don't know the model #) the cable that connected to the speaker mic it self, used a RJ45 connecter under the rubber boot, you can simply get a Cat5 cable and put a 1/8" plug on one end to plug it into your comp. likewise, if you want the coiled cable, simple cut off the radio connector and throw on an 1/8" connector.
If you don't like my HONEST opinion. Then don't read it. That is all.