So far the block logo guitars that have popped up in the flesh have been ST50/55s and TE50/55.
Wondering why I am not seeing higher priced models? The '83 price list shows all the other options available. Odd.
Colors so far:
ST50/55 - FO, MR, SO, PB, GM (matching headstocks in MR and SO)
TE50/55 - WR, MR, MB, BL, GS
I missed your q before, but here's my experience and understanding:
* before 1983, the '7okai' logo was on all F-style vintage copies. It was on the guitar reviews I saw back then.
* in 1983, I buy my first Tokai. I order it unseen on the strength of the stellar guitar magazine reviews. I was given a price by the guitar shop - no options or spec levels at all were offered. When I get the call it's a
vintage red (not FO/MR/WR - a blood red more like Fender's Dakota red) Springy Sound with the 'BLOCK' logo on a matching headstock. I'm a bit miffed by the altered logo, but happier about the painted headstock
* in 1983, for reasons I've never seen explained, Tokai changes the guitar's name to Goldstar Sound. Later comes the altered headstock shape.
* in the 1990s, I often searched Loot (UK classified paper) and Guitarist magazine classified section for high-end Tokais - never saw one. At this time I met another Tokai collector (Lee something in London), he had the same experience. Also spoke to Todd Sharpville when he was looking for them - IIRC, he was chasing many Tokai adverts in the UK and a bit fed up of finding the same ST-50/ST-60 guitars with/without matching headstocks.
* so, during the 2000s, I searched many Japanese shops online and bought a pre-1981 '7okai' ST-80 and TE-80 direct.
* I never saw a 'TOKAI' block logo during those Japanese searches, which made me think that it was a UK/Europe-only change
My gut feel is that in the 1980s the UK importer chose to import only the low-end models, and perhaps very few ST-80s and ST-100s. And so it's a coincidence of 'BLOCK' logo at a time when the UK/Europe got only ST-50/55/60.