This is another mystery pipe. The bowl appears to be of the same material as the Bryson, i.e. compressed wood powder. Cannot make out it eh bowl retaining screw is steel or aluminium (Bryson used steeel, Kirsten used alloy. The stem has much of the look of a Kirsten, but the nose cap seems Bryson. The push rod could be adapted from either. Hopefully someone can come up with the answers, but until then I file it in my mind as a home made conglomerate.. Many folk seemed to have the necessary machinery and expertise to amend these metal pipes.
In the meantime a search of the US patents may bring something to light, since it appears to be stamped "pat pend"