Did you read the Kernel's post?
To go more in depth, the answer is no, you probably shouldn't use stainless (although I'm not sure what you mean by "seasoned".)
From Brownell's advisors:
Bluing Salts in the presence of stainless steel and gun steel frequently can create "galvanic" action (electric current flow) between the two dissimilar metals resulting in a "false plate" of either chemicals (streaking the bluing with random iridescent blues/greens/purples) or stainless steel (giving patches of random silver specks/spots).
Black Iron tanks are fairly cheap:
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