They are to be commended for the incredible work they are doing, with extremely limited resources. Considering the standard of living in Cuba, the fact that these guys can keep up such a level of maintenance on these aircraft is a credit to them.
The idea that those of us in first-world countries have some 'right' to go and cherry-pick certain items from collections in other countries smacks of arrogance and self-righteousness.
This Cuban group (and those who look after the examples in the Philippines) have ensured that these machines are still around and are being looked after. We have the luxury of being able to buy spray equipment and other tools, maybe they don't.
Perhaps the Cuban Mustang had its canopy smashed. The replacement isn't ideal, but it's keeping the weather out. Anyone wanna send them a replacement?
Anyway, it's dizzy up here on my soapbox, I'll step off now
Cheers,
Matt