The real Canon hoods show up reasonably often on eBay, and so long as they come with the 40mm threaded adapter (on the round one) or the 42mm slip-on or clamp-on adapter (for the rectangular one), you're all set. That's because when you unscrew the hood from the adapter, there's a place to put one Series VI filter.
On a 7, the round hood should not be as intrusive as it is on the II. III, and IV series cameras. Still, the rectangular one is the best.