Confirmed, Koetsu Urushi
Hello spillage,
yes, it is an Urushi. TMK, there are 4 variants: a red one (Vermillion), a black one with & gold spots (Black), a yellow one with spots (Wajima) and a yellow/white/black one with lacquer layers mixing with each other which i believe is called Tsugaro and to me it looks like you got this Tsugaro.
TMK, the lacqering does not indicate quality levels and "Urushi" is one model, one quality level.
Anyway, i also own an Urushi Tsugaro and TMK this variant is no longer made and dates back to the late Sugano senior. Which means : it something you should take well care of because it is a crown jewel.
I have listened to Onyx and Onyx Platinum, i prefer my Urushi Tsugaro. It is the live-liest Koetsu i know.
I would recommend a top-notch step-up amplifier or step-up transformer like the Jensen JT346-Ax, wired as 1:12 . I currently have no cartridge data at hand but if you really pester me, i will have to look for them.