Mizuho MX2
The MX2 was a 200mW 2m SSB handheld. It was capable of working some impressive handheld 2m DX. I used mine with a halfwave whip antenna.
At home it was used to drive a homemade 10m QRP transverter and worked worldwide DX with 1W pep SSB and a wire dipole. The operating bench looked very small! I still have that transverter somewhere.
Other versions were available for 6m and 4m.
See https://www.radiomuseum.org/r/mizuhotsus_2m_ssbcw_transceiver_mx_2.html
The main issue was battery life. This was poor and I used mine with an external 9.6V rechargeable battery most of the time. I suppose the lead to the battery acted as a counterpoise.
I am pretty sure these are no longer available new. By modern standards, these were not tiny. Perhaps you may find one on eBay?