A quick update.
Thanks to those who sent pics of intact rollers.
Derived from those the correct pinch roller diameter is 27.20 mm.
Notes here:
http://everist.org/NobLog/20180922_data_in_holes.htm#rub
It seems there's a few people who need new M200 rollers.
Once/if I perfect a successful method of making replacements I'll
offer them for postage and a few dollars. But I'm in Australia.
Or, there's this guy in the USA:
http://www.terrysrubberrollers.com/
Now the correct OD is known he's an alternative, with real rubber.
(Maybe my end result will be rubber too. That remains to be seen.)
I still haven't found a service manual for the TM200 (with schematics.)
Guy