Well i have one off those.
Its a hybrid off the old mod 55 and parts from Weihrauch.
And what i know they only did this from 85 - 86 maybe a little longer.
They stop when the parts came too an end.
Weihrauch also make the Venom model and its the same with that one, some BSF part and some Weirauch part.
I cant post any picture here so send me an e-mail if you want to see this "new" 55 model.
Andy