I know that made this same basic type in many countries and there are different versions.
Some of the best are from Japan and some of the worst are Chinese.
Before the CEPA banned the import of the non compliant types from China a lot of very bad engines were sold here and people will not touch one from Asia now even if it does say Kubota.
Another problem Most of the Japanese will not support these engines if imported to Canada.
They will not sell you parts to an engine with a serial number that complies to a Canadian product ( this is to reduce competition from used imports )
On the other hand if you buy an Andoria, Farrymen or one of the other well known brands from Eroupe you can buy parts for dealers and get them imported.
Its harder the other way around from Asia.
I buy my Honda parts from a dealer in Thailand.
Duetz is not very happy with me because I imported clone FLW912 clone from KOEL and sold them as knock down kits and parts.
Their dealer network will also not support licensed product form Asia ( they really do not like me, serving me with a cease and desist order in 2004 )
I think the design can be traced back to Duetz too.
Interesting to watch you can see this is a match light engine and needs a burning wick to cold start.
Some of these engines use a pre-cup Recardo type combustion chamber ( easier to cold star )
Some use a DI head and these are better for dual fuel and wood gas. ( Andoria types are DI engines )