There isn't one that matches perfesctly. Floquil Polly Scale S.P. Scarlet is the closest. Funny that comes up now. I will be spraying the end of a long hood today. When adding gyra lights I usually use the Polly Scale and just brush it. Red is a hard color to get good coverage so it will take several coats.
I used Floquil and poly scale for my sp h.0. stuff. On one model, I mixed my own using some formulas I downloaded off the net. I checked out my bookmarks to see if I still had the link, but it appears to be gone. You might try a search on google for S.P. paint schemes. I seem to recall that's how I found the formulas.
BTW, they worked ok, but unless you have a really, really good eye, the standard sp greys and reds from poly scale and floquil work just fine.
Floquil SP Scarlett and Floquil Lark Dark Gray. Even with the prototype, there occasionally was some variation in color hues. I model the older colors like the black widow or tiger stripe, but the SP modelers site recommends these two colors for the "bloody nose" scheme.
I was using those PolyScale colours but the dark lark grey just didn't seem light enough to match the USAT paint. It's a pretty good match but when you're up close to the loco you can notice a very slight difference in shades.
Here is where I've got to so far, still needs a few couple more decals (the "F" on the front end) and a good weathering job:
Sorry the pictures aren't great, will try and get some better ones soon when the weather clears up and I can run outside!
Most of the weathering is done with an airbrush and Polyscale paints thinned down about 50% with bottled water. Just go slow and have the brush adjusted so only a very small amount of paint is being sprayed. Its easy to keep going over the model until yopu get it the way you want but hard to fix it if you get to heavy with it. When you start thinking it is enough then stop because it probably is enough. I have about 5 or 6 colors mixed in small jars so I can switch colors easily. Dirt colors,grays,grimy black and oily black. Practice on an old freight car until you get comfortable. Main thing is go slow with it. I still get a little nervous about weathering a locomtive that I have spent a lot of time detailing,but it always seems to work out.
The speedo on the right hand side truck is an Ozark part, I just snipped off the end and replaced it with a length of paper clip as the wire wasn't long enough to reach up to the loco. The rest I made out of styrene, sadly no one makes these bits in 1:29, plenty for the HO folk out there, but sadly not many for the large scale SP guys. Ozark do make a few bits and bobs that are worth checking out, but none that I could use for this geep. The red emergency light has a red MV lens in the centre.
Even better for airbrush practice is to spray a soda can black and practice your trigger control on it. I did this long before I pointed my air brush at a model. Get photos of the real thing to see what is weathered and how much. On my SP models I use a lot of Earth, Grimy black, Rust, Roof Brown and Dust. I also use washes to simulate diesel fuel spills on the tanks and water spills.
I don't know, your model looks pretty good to me...the colors are okay, what is the big deal is the lighting where it will be viewed. What looks good outside is often way off indoors; SP gray being good at this. I like what I see though; well done.
I think I've proboably just being looking at it too long! I got some more shed time tonight so I filled in the space in the pilots round the coupler draft box, looks so much better without all that empty space! I'm just peeking out the window and hoping that the rain and hail over here will eventually pass over so I can get out and get some action shots. Scottish weather is just so awful!