If you can't find one, take a look at the REC Components version that connects together using high strength magnets. I just got one. While i have not done a river test yet, it snaps together quickly, one-handed, is very sturdy, and comes apart manageably (without the need to press a detent button). Based upon construction and design, I believe REC Components makes wading staffs for Orvis and made the old Simms staff that you seek. If you have an old Simms staff in need of repair, it may be worth contacting REC. If they did make it for Simms, maybe they will repair it. I sent my old one to Simms after they assured me it could be repaired (the wire had frayed) and they simply destroyed it and sent me one of their new adjustable staffs.
I can't understand why some folks think a drink can is harder to carry out when it is empty than it was to carry in when it was full.