Plug caps for early Honda?

[rbaselt]

Has anyone run across straight plug caps similar to the ones in the attached photo? They are from a 1962 Honda 125cc twin, and are roughly 0.75" diameter and 2" long without their rubber protective covers. They are a non-resistor type for 10mm plugs, and the top unscrews to allow soldering of a flat round steel contact to the end of the HT lead. Thanks, Randall