Good day Ralf! I have one of those "telephone dial" rails that came off of an early Mercury bass drum that had "Fibre Gold" wrap on it. Pearl never used that wrap colour. As for the strainer, it is possible the distributor had these made and sent directly to Star, (in this case I am almost certain it was Brooklyn Music Supply that owned the name LaBoz) or installed them once delivered to their warehouse. Dixie also used this strainer as did only a few other of the oval brass badge name brand stencils. LaBoz always used the plastic badge, which I believe they made, or rather had them made and sent them along to Star or applied them once the drums were delivered to the Brooklyn Music warehouse.
This rail type was only used on a few name brands. The "dial" type parts were not as reliable as the others. There is no question, in my opinion, that these early LaBoz are Star. I see no other parts I can attribute to Pearl, although I do know that LaBoz, Dixie and approx 3-4 more names did use this strainer design, but I am fairly sure these are custom parts supplied by the distributor in order to differentiate themselves from the others.
When I try to identify stencils, the main parts I take into consideration are the lugs, then the strainers, then hoops and sometimes I will have to go as far as to look inside the shells if they are later 9 ply shells to see if they are painted grey. Sometimes the snare lugs are the only clue as to who actually made the drums. These lugs, on the snare and bass are definitely Star "Type A" lugs. Also, see this catalog page for the rail type seen here.
http://www.tamadrum.co.jp/anniversary/expansion.php?cat_id=5&now=7
In this scan, we see the lugs yet again and also the bass drum T-rods. Pearl did not use this type of T-rod.
http://www.tamadrum.co.jp/anniversary/expansion.php?cat_id=5&now=10
This is how arrive at my identification conclusions, taking as many factors into account as I can find