The Orval strain is released commercially by White Labs as part of the May/June platinum series as WLP510. Ferment like normal, then add Brett Brux. in secondary and age.
I'm really interested to hear someone repitch 9097 from a banked source. I am very curious to see if any growth rate differential between the Sacch. strain and Brett component effect a "second generation" beer adversely or not as I am not totally convinced it would result in the same product - analogous to Orval dregs out of the bottle (where I would think most of the Bastogne Sacch. settles out before the bottling process, so I would assume you are pulling more of the Brett if bottle harvesting).