I need to amend my previous statement a little, which doesn't affect your situation at all. Just for the sake of accuracy.
1) That Swiss shop's stamp was NOT "AR". It was "GH". See the image below. They must have done it to every pipe they sold. Even very expensive Former pipes have been seen with it. Also, you'll see some misinformation about this on the pipedia pages, saying it was possibly Harvey Grief stamping his own collection of pipes. I should probably report it and have that removed. I think it started when I was asking about this stamp and doing some research behind it.
https://pipedia.org/wiki/File:CaminettoArticle2_HarveyGreifStamp.jpg
2) I believe Ascorti also had this Caminetto shape you're trying to sell.
3) here is another example of the pipe you're trying to sell, though this one appears to have a replacement stem with a not-very-accurate wings stamp
View attachment 11935