Are you using the DVR module? Because this would be very suitable for this. If not, how are your files named and how precise do you want users to be able to search? A specific minute or even a specific second?
If you did not use the DVR method the most easy solutions would probably be to cut the recording in to files of one minute and concat those with a dynamic playlist. Just let me know if you are still looking for a developer to develop this. You can send me a direct message or e-mail me directly at wowza [at] kayenta [dot] nl