[Hallicrafters] A unique SX-28??

[Bill]

Would anyone have any information on what appears to be a rather unique
SX-28?
The unit in question uses a knob with a metal pointer for the bandchange
knob.
I might have thought someone replace the original bandchange knob with
this except
that the panel has a small post which prohibits the band change knob
from rotating through 360.

thanks
bill, ve3jhu