Δαφνη Ευτυχια Αρθουρος

What's a reasonable rate to charge someone who wants to republish a story I wrote on their own porn site?

What's a less-reasonable price to charge for the privelege of removing my name from the story and presenting it as if it were content developed by, or specifically for, that web site?

How unreasonable should I let myself be, considering that they decided to skip such steps as negotiation, asking permission, etc. and I have no idea how long my work has been on their site?

Or should I abandon all pretense of expecting them to pay me for use of my work, figure that they got away with using my work without paying for it for however long, and just send a DMCA takedown letter to try to stop them from continuing to do so? (But if I do that then I need to be prepared to sue in case they try to resist, right? So first I'd need to find a lawyer who'd take on a copyright infringement case on contingency ...?)

Having my name removed pisses me off more than anything else, because this way I'm not even getting credit, in addition to not getting paid.

(The story in question is, of course, "The Chastity Belt", the third most popular page on my own web site. A few years ago it was #1 on my site; I wonder how much of its drop to third place is because sites placing higher in search-engine results are sucking away readers from my site.)