Yeah I’m quite new to Hermes. While I’m not the greatest fan of their bags I love their RTW and Shoes. So timeless and easy to match with other things and seasons.That date sounds about right, those buttons wouldn't have been before. Interestingly there's no AW03 showing on Vogue Runway. I'll check with work's digital archives and let you know if I find anything. I have a 6-ply orange cashmere sweater from the turn of the Millennium, the great thing with MM era is the pieces all work together from other seasons of the same era. Same goes for JPG era too (my favourite).
I don't find 2003 'old', I have plenty of 40, 50, 60, even 100 y o coats in my 'archive' that knock the sheen off anything new, even at H. Your coat is a real find among coats, just fabulous.
You’re right „old“ is the wrong word. I’m not a native speaker, but what I’m trying to say is that the coat could be from this season or 20 years old it’s so timeless and you wouldn’t think it’s over 20 years old if that makes sense!