As much as I LOVE the 7x30 Waters, since you are shooting an Encore, I'd go with the 7mm-08. Cartridges are easy to find, and it's a very good round for deer hunting, especially at the ranges you describe. Factory 7x30 Waters ammo is almost non-existent in my part of the country, and when you do find it, it's mostly leftover ammo that was designed for use in lever guns (flat point). It's not hard to make from 30-30 brass, but since you're not a handloader, this will not be an option for you, and you'll be forced to scrounge for loaded ammo.
I's say go with the 7-08, UNLESS you opt for the handloading option. I don't know if you know this, but you can purchase one of the Lee handloaders (the type that does not mount to the bench). It takes standard dies, and does not take up any more space than a hammer. you could have you a bin about 18" square and keep all your reloading supplies in it. That's what I used to do before I got the space to set up a bench. All you need is the dies for your caliber, the little hand press, primers, bullets and a can of powder. If you use Lee dies, the die set even comes with a little chart and a dipper for the powder charge. The Lee hand press will definitely give you an upper body workout, but all of your stuff will nearly fit in a shoe box! Check it out....
