Make friends with you local publican and you'll have a ready supply of champagne bottles perfect for brewing or bottling sauces. I get a steady supply of bottles from my local club. The beauty of the champas bottles is their strength, they can take much higher pressure than your standard long neck.
They are wider, but most bottle cappers can have the wider capping bell screwed onto them and champagne bottle crown seals aren't that much more expensive than the standard ones. I think the wider bell was about $5.