What can I tell you if you donít like my experience with it. Did not always fully cover in one coat, left brush lines, came up or shriveled with second coat and easy to peal off. And add that it drys to fast. Now that is my experience with Tamiya. Maybe you have the magic touch who knows. And if I remember correctly it is advertised as brush and airbrush friendly. Not for me it wasnít, nor were there pigments accurate so off to proper recycle they went. See I donít work the paint, it works for me or gone.
As for Polly Scale Railroad paints have you attempted to look? Or are you making an assumption based on its age? Lot of model railroad cars and equipment come pre-painted these days. Left many a hobby store and internet store holding inventory. Because it is not at your local hobby store does not mean it can no longer be purchased. I purchase far a field than the LHS. Military colors are rarely found new but when found are sold at double or triple price. I am game because the paint even 20 years old doesnít give me the headache some paints did including Tamiya and Testors.
Polly Scale RR colors still not difficult to find but getting there. Mostly all the blues are gone. Grays, reds and green pigments still can be found at reasonable price for 1 oz. I like to think I know what I am talking about for I have extensive collection of Polly Scale and some Testors USN naval pigments.
My collection is too important to me to start changing brands of paint and then possibly pigments as well.
Gunze is sold here in the US. Search the net for I do believe there a few outlets who do sell it . Just canít when and where I saw it. Too fast a drying paint for my taste.
As for Kure Naval Gray a quick Internet produced one hit of sale.
Since Polly Scale RR has been discontinued for over 5 years I suspect that availability will also be as much a problem as for Testors. No paints are cheap in today's market. I'm also surprised that Tamiya must be used with a primer and is considered by you to be more of an airbrush paint. I returned to modelling about 35 years ago and have used Tamiya paints for about 60% of my hand brush work during that time. I rarely use a primer and I mask it all the time and it adheres very well.
In my opinion Gunze Sangyo Aqueous paints are the best paints out there for either brush or airbrush, but availability is a huge challenge. In Pennsylvania we still have hobby stores and I can always grab Tamiya when I need it.
Testorís paint maybe hard to come by being a naval paint. It wonít be cheap and will be in semi gloss. Tamiya I never liked. It will not adhere without a primer and advertised for brush but really airbrush.
If you are a die hard IJN builder may I suggest you take your chip card and match it against Polly Scale Railroad colors . I have done that for Modern USN Haze Gray, 20B, Modern Deck anti-skid and 5N. Many Polly Scale RR grays are still available/in which hobby stores are dying to unload.
If I recall Kure Naval Gray was a very dark and deep gray. Polly Scale Neutral Gray or Guilford Gray as suggestions available on evil site. Not inexpensive but a lot more friendly to brushes.
Tamiya and Testors both have a Kure paint that are suitable for brushing Tamiya also has it in a rattle can..
I see where Scalecolors & Tru-Colors both offer this color of paint, but appears mostly for use in airbrushes. Can they be applied by brushes with acceptable results or is there another brand out there, that would work better?