What's the story there @DonGiles? It looks like an Everyman stem but I don't think they did sandblasts.
To the OP - always evaluate Dunhill "filter" pipes from that era carefully. Many are represented that way, but are not true filter pipes. Dunhill used a tapered aluminum tube in those days and at first glance, it may appear to a filter hole in the tenon. They do have an open draw without the tube, but that seems to have a strong appeal with many (I like a somewhat restricted, typical British draw like on Comoy's/Dunhill/GBD, etc.). You might like it! I would guess Mkelaw would know the difference.