I think what you have is fine.
However, you might consider instead having a yellow triangle with an exclamation mark in the middle, and when the user either clicks on that or hovers over it, have it show what it's warning about. For now, it could just say something like "Unofficial Part", but in the future you could add other warnings. Or, you could give more details in the warning, like you were asking about.
However, you might consider instead having a yellow triangle with an exclamation mark in the middle, and when the user either clicks on that or hovers over it, have it show what it's warning about. For now, it could just say something like "Unofficial Part", but in the future you could add other warnings. Or, you could give more details in the warning, like you were asking about.