Status really important, agree. I will go as sovereign private individual, make more sense to me and not sure what how my response could look as commercial part.

This sticker will be really useful, thanks! I'll just need to translate it in the local language. The other fact is that there's no sender in the envelope. Only inside the letter there's an address specified in case of complaints, and that's where I'll send it.

Another detail is that I want to guarantee that my response will be delivered, so I was planning to send it back as certified mail. This stamp will be definitely a good addition!