DISRAELI GEARS
On the face of it this is just another Taiwanese copy of a Shimano Skylark/Tourney - aside from the mysterious brand, there is little obviously interesting about it.
However the swivelling adjustable outer cable stop, and the adjuster screws with springs to stop them loosening (rather than the later plastic piece) suggest that this could be a relatively early Taiwanese derailleur. Shimano had stopped using both of these features by 1981 (see the Shimano RS). However, the cable clamp is on the outer parallelogram plate, and Shimano did not start doing this until 1981 (also on the RS).