Hi Becky, welcome to Multitool.org!
I don't think I would exactly classify this kit as a "knock-off." Interchangeable-blade knife & tool kits like this were produced by many different companies, over the course of many years. The two you mention, Hubeo and Dreizack, were certainly among the better quality offerings. However lots of other companies, including cutlery firms from France, Great Britain, United States, Japan, and other countries also produced kits, albeit with varying degrees of quality.
Judging by the looks of the kit you pictured, the plastic lining, and the fact that there are no tang stamps on the tools, I would guess that it came from Japan in the 1970's. (German firms were still producing knife/tool kits at this time, but they were typically well marked, whereas Japanese cutlery from that era were either unmarked or stamped only with the name of the importer.)
All pure conjecture on my part though....hope that helps!
Bob