Yeah, please don't offer money for anything on this site. It's against the rules and could quickly lead to a ban.
That said though, I hardly think HA Mareanie is worth a shiny and/or valuable events. While 'worth' is in the eye of the beholder, Mareanie is a staple competitive Pokemon and is in the inventory of most serious breeders. In fact, they're common to the point where I got three of them while Wonder Trading half a box of Pokemon a month ago.
Anyway, it sounds like you won't be able to accept the offer above; I might be breeding a shiny one soon, so if you want a spare breedject just let me know.