Wagner suggests a 66mm (diameter), 2mm width would be a fit:
https://www.wagneronline.com.au/pana...-4405/1081/pd/
same with this australian site:
http://www.telespares.com.au/index.p...ucts_id=311582
Dönbarg redirects to 69mmx2mm square for the part number (which is the as used by 2000s LG, Samsung, Daewoo and probably other brands too):
https://www.donberg.ie/catalogue/vdv0382.html
Not sure which is correct.
The text on the donberg site, and the text on an official replacement part bag in
this blog post about fixing a related japanese model with the z mech says "3mm" rather than 2 so maybe these sites just list the closest available (which may be fine.)
The same mech is used in a lot of cheaper models though, including NV-FJ, NV-SJ model plus the newer NV-SD and NV-HD models, and other panasonics from the late 90s to early 2000s so that may also be an option.