Keep it as simple as possible...the scope and the right rings should be all you need, unless you want to move the scope forward some. On a standard flat top with no extension, the eye of the scope will almost certainly be farther back than *some* folks like it, and the longer the scope, the furhter back the eye is, obviously. At 14 1/2", that Leupold is pretty long, so you might be a problem for you.
The Armalite on piece mount and the LaRue mounts will move the scope forward...the RRA does, but only about 1/2", which is next to nothing, really.
The LaRue is a very nice mount, but it's $200 or so, a little more if you get the EER version...and if you're stretching your budget with that scope, you might consider another solution, like the Yankee Hill Rail Extenders. They also act as a riser, so you could probably get away with low rings if you're gonna go that route. ARMS makes rail extension too, and I've seen several on the EE lately for pretty cheap.
It sounds like you'll have a *very* nice rig when you're done, and I'm sure marmots everywhere will fear you.