This Buchla-format module can hardly be called a "clone" as it only has a passing resemblance to the 258e Frequency Shifter/Balanced Modulator. The Timbre Sculptor 2060 is essentially three modules:
1. two ring modulators
2. a four input mixer
3. resonant lowpass gate
I have no idea which furtive Buchla clone builder created this hybrid, but it has nearly the same skittish nature as its nervous father.