19300-KV3-701 is the correct part number for the thermostat.
37750-PC1-004 is the temperature sender for an mc21.
37750-KV3-951 is the same part for an mc28.

The thermostat is priced at 2100 yen in the original parts manual.

So that makes it around $33NZ in 1993....
_________________
Please do not PM me technical questions, if you can't find it on the Forum start a thread