Not sure exactly what brand/kind of paints you have another thing you could try might be a reddish brown (chestnut?) ink wash over a steel color
In my case, on my 1/72 Sea Dragon exhaust tube (or whatever the technical name is) I used P3 Brown ink (which is actually a very red/chestnut color more so than brown) and Army Painters strong tone wash over Army Painter Durasteel (although any mid range silverish/steel color would work. )
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You theoretically could take the same approach with washes/glazing using similar acrylic paints you have (not sure about enamels). The "glazing" technique is like staining more than a wash that settles into low areas. I do it by mixing in some glaze medium (Vallejo). Inks just make it easier
here are some shots in different lighting of the effect. I also did it in several thin coats. Hard to tell in these pics, but you can get the uneven "splotchiness" which helps add to the effect
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