If there is, it won't be a legal download.
Apple did have a trial version on its website at one time, but it's long gone. That was the only legal download available. The application continued to work, but would not Save or Print after the trial period ended unless it was activated with a purchased key.
You might be able to find the boxed version on eBay, Craig's List, or similar sites.
BTW: Mine was one of the early boxes, purchased with a Family Licence shortly after Pages '09 was released for CDN$99. It's now installed (and updated as necessary) on three Macs running three versions of OS X (Tiger, Leopard and Mountain Lion). Works fine on all three.
Regards,
Barry