Well, I discovered this topic today and I'm a bit disappointed to not notice it before.
Even if the idea behind is great for players, I'd like to avoid the promotion of 'money transactions' on osu! forums.
The thing is you can't trust someone who's doing stuff under the table like that, he's not a company so he can do whatever he wants.
You're paying him at your own risk and we don't want to have osu! related to this, you can understand that.
The only place which is 100% trustable here is the osu! shop.
If you really want a tablet cover, I ordered one to someone who was really active in the osu! community before (not that much now but yeah).
I link you his twitter page where you can find information about it :
https://twitter.com/horocchi . I'm not leading you to his tablet cover stuff directly because osu! forum isn't the place for that but, at least, I help you a little bit. Don't forget this is something you do at your own risk.
If you have any question, feel free to contact me through PM on the website or IG.