By the way, I asked Mr Snape about Mysteries, since I know you're interested, and whether the Order knows anything about what would be useful for getting a job there. He didn't really know. He says that in the past, they recruited some generalists who were interested in everything, and specialists who were totally obsessed with some particular thing (like poor Capper with Arithmancy -- if he hadn't been a half-blood maybe that's where he'd have ended up.) But that was a LONG time ago, anyway.

Have you thought about asking Mr Malfoy? You got that tour all those years ago and met Mr Rookwood. It wouldn't be suspicious if you told him you've been thinking about that again.