Most holster manufacturers list the guns that will fit a holster, and since the 709 have been out for a couple of years now I don't think you will have a problem finding something that fits.
However, just because the gun fits the holster doesn't mean you will like it since there is more to it. Some guns ride higher than other, some has a cant that make them easier to remove, some has a sweat guard, some have belt loops while others have clips, some just don't feel comfortable and I am sure there are others as well. It's a lot of personal preference. Most people have more than one holster for their carry gun until they find something they are happy with :-)

