The machine in the video was made by Sanyo in Japan and sold as their model ICC-0082, but this particular exemplar was marketed by Dictaphone in the U.S. as model 1680. Other than the nameplate, the machines are identical. The Sanyo calculator was announced in May 1970 and sold in the U.S. for US$ 425 in 1971 (around US$ 3100 in today’s BidenBucks).
The displays are not Nixie tubes, but rather gas discharge seven segment displays. The calculator is implemented on four integrated circuits which were designed by General Instruments in the U.S. and manufactured by Sanyo under license.
Here is more information and photographs of this calculator.