Precision doesn't identify their builders like PBL, W&R and others.
I don't know when the C&S 2-6-0s were imported, but the most likely builders were late Samhongsa (before they closed up shop) or BooRim. Every BooRim model that I own runs perfectly.
I bet Jimmy Booth (at PBL) would know. He also imports his own brass under the trade name Glacier Park Models.
There is a nice Key C&S B-4-E # 71 currently listed on eBay. They were made back in the early 1980s by Samhongsa. I owned one (before switching to Sn3) and it was the only C&S HOn3 engine that ever ran very well.
Wayne is a C&S fan who has been working in HOn3 since the 1970s. He has developed micro-motor re-gearing sets with fly wheels for virtually all the HOn3 C&S models (PFM, Westside, Key, Lambert, NWSL Spartan series, etc.), as well as many older HOn3 D&RGW models. I was always amazed at how he could make an HOn3 locomotive crawl and not stall, when I would visit him at his old hobby shop in Houston, TX.
Give Wayne a call. I'm sure he knows the ins and outs of all the later Precision Scale HOn3 imports.
I had found LocoDoc on the web, but he didn’t list the PSC C&S 2-6-0 in his “proven conversion examples” page. I wasn’t sure whether that meant it didn’t need help, wasn’t interesting enough to bother with, or was beyond help. ;)
I spoke to Wayne at Roundbell/LocoDoc on the phone today. He said he hadn’t spent much time with any of the PSC models, and had never come across the C&S #9. He thought they might be made by the Korean company that used to be called “...”, but the connection wasn’t very good and I didn’t catch the name he mentioned.
(He did say I had the right email address, so I’m not sure why he didn’t get my original query.)
Just to update this thread, I dropped off my PSC C&S #9 with Wayne Weiss last weekend for DCC installation. He opened it up and found a Mashima motor and what I think he said looked like a NWSL gearbox. In any case he said there was no point in upgrading any of that -- it'll be a good runner as built. He also seemed quite impressed with the level of detail on the engine.
He was less enamored with the full coal box on the tender, which will have to be cut out for the DCC install. The tender is also quite narrow for a speaker, but tall enough that a keep-alive should fit along with the micro-tsunami.
His shop was a treasure trove of new-old stock. Sadly most of the narrow gauge stuff was already on route to the convention, and my daughters were about done waiting on Dad, so I didn't get to do much shopping.