RB67 lens--screw for MLU

Hi--I have a 65mm k/l lens for my RB, and there's a little bracket around the MLU thread that's held down by two tiny screws, one of which has gone missing. Does anybody happen to know what size screw to use as a replacement?

Not sure what size it is but I am sure I'll find a few in my junk box. If I had the screw I can match it up for ya. See if it is the same size as the flash PC screw? If it the same mail me the screw, I'll send another the same size.

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