I had several targeted letters come from one person. Each has its own envelope, each school's address was at the top of the letter, and the back of the envelope had the title of the targeted letter.
Hopefully that will be enough.
As for checking on them, I dont think we can. Maybe you can call to double check? I am not sure if he person on the phone will be able to see the scan though.
I'll let you know how it turns out.