What was the string bed configuration? 16x19 or 18x19? How thick was the beam? Have your buddy measure the weight, balance, beam at tip/throat. If he can get it, also the SW. This will give you somewhere to start when looking for comparable frames.
25 years ago, the old Head model line did not include any blue Rad OS that I can remember. You could post a picture in the Classic section asking for help identifying the frame. Sounds like a Vista or Ventoris 660, but can't tell for sure w/o picture assuming it's a Head. Could even be the re-issue of the Atlantis or Genesis 660.