This handkey was made in Japan and appears the base is an original from the factory.
The key fits snugly in the base held by two screws.
The base measures 4 1/2 inch's across and weight about five pounds.
The Hi-Mound HK-702 is a deluxe hand key any amateur would be proud to own. It measures 3.5 X 3.6 X 5.75 inches, weights 2.2 pounds, and has a beautiful chrome and silver mechanism set on a glazed marble base. A rubber cushion is fitted around the base edge for solid "stay put" footing on a desk. The key has silver contacts, easy adjustments for gap and tension, a skirted knob, snap-off dust cover, and a very smooth feel during use.
Hi-Speed Hand Key Model: HK-100. The base measures 6" Long X 3 3/8" Wide and almost 1" High. The knob is 1" across and 1" High and has felt on the bottom to help keep it from sliding. I assume it was Mfg. in Japan although someone wrote Korea on the box.