I took a shot at ordering more metric pan head micro screws last Saturday from https://www.microfasteners.com...rection=0&page=1 for replacing my Lionel metric black oxide 1.9mm X .4thread X 8mm in the smoke unit. I got a 50 count bag of 2M X .4thread X 8mm and they arrived today. These are stainless (didn't see any black oxide metric on their site) and not magnetic; their heads are a tad bigger; they fit the threads exactly in the smoke unit with no resistance to screwing them in and they do hold. So, in a pinch I think these will work fine. Also got a bag of the same but 10mm in length.
MartyF, got yours today - thanks a bunch!! I have sent a set of 5 each of the above to you.