When I see stuff like this, just makes me wonder if stuff completely gets cut off, what spare parts can't be replaced without their help. Not the same industry but China did keep S-70 operational long after America stopped supporting them.
Keeping the S-70 alive probably created the foundation for the Z-20. All those parts needed needed to keep
the Sino Black Hawks running for decades must have been a cottage industry on their own. When the domestic project started up, a lot of the components were there.
The MD-80/90 tooling at Shanghai helped give rise to the ARJ-21.
I can bet the farm that if things get cut off, it'll simply be produced inhouse.
Foreign companies prototype in China because of the industrial eco-system that can reproduce everything.