Would this work?

Did you ever see the ads for "Dustless Blasting". Maybe just call them and let them do it? But, yeah, if you have a good place to do it and don't mind getting dirty, it would be cool to have a machine like that! (BTW, if you are worried about flash-rusting, Dustless sells a rust inhibitor).
Dustless Blasting® - The Future of Surface Preparation®