If it is truly "Stainless Steel" (not simply "in the white") then it probably will not take a traditional gun blue. I have had very good results with "Aluma-Hyde" from Brownell's when used on SS. I clean the parts with denatured alcohol first then hit the parts with a heat gun for a few seconds (not to heat the parts but to dry any remaining alcohol and get the part just above room temp so I don't trap moisture between the finish and the metal. Apply the "Aluma-Hyde" as directed on the can, let it fully cure (I give it a week) and you should be good to go. I have used this product on a SS Mini-30 and a SS AR barrel. Both still look sharp.
ETA:
I just re-read your post. "Aluma-Hyde" is a paint so I don't know how well it would work on threads if you actually intended to install (and remove) a legal supressor or fake can, MB, etc.