1. The PCV is from a 2003 VW Passat 1.8l turbo(??)
The generic part is BECK/ARNLEY 0450392 from Rock Auto $23 minus their usual 5% discount.
2003 VOLKSWAGEN PASSAT 1.8L L4 Turbocharged PCV (Positive Crankcase Ventilation) Valve | RockAuto
2. the 'catch can' - I am assuming that a generic EBay can 500 to 750ml & made of aluminum is the best choice. A design with an un-screwable cap is easiest for fabrication? Most have inconveniently positioned fittings that require modification or plugging:
Universal Silver Round Aluminum Racing Oil Catch Tank Can | eBay
The Mishimoto & Moroso cans seem too expensive for an experiment?
3.The various barbed fittings : - I prefer using brass & source from "Fast Fittings" because I can usually find everything I need on their site:
https://fastfittings.com/
For this application, here is a good place to start because it gives the actual(not just nominal dimensions of the fittings:
https://fastfittings.com/collections/brass-hose-barb-fittings
4.The stainless steel wool (coarse) is here in abundance & made in USA!
1 lb Stainless Steel Wool Roll Coarse Great Forexhaust Muffler Repacking | eBay
What we also need is a specification and source for the absolute best vacuum lines - both the hard line and the softer grade.The OEM items usually become brittle.Any improved AOS is only as good as the next weak link!
I prefer to avoid using what is described merely as "plastic" tube and try to find a specific high performance polymer to avoid deterioration and leaks in future.
Tygon tube i one candidate ? I tried finding something better than SAE J30R7. 30R9 is too stiff & thick?
I hope this info and some of the ideas help move this project along for others who will follow.