To be blunt, you probably aren't going to be able to do that.

The linkage is downwards. The data pages link to the text pages (and there can be multiple), there aren't backward links. Unless you know SQL's page structure, allocation mechanism, pointer format, etc backwards and want to spend the next week or two in a hex editor (not joking), you may have to settle for using DBCC Page to view the data, copy it piecemeal out into some external tool and run repair (it will deallocate all the damaged pages)