$600-800, Wow! The reason the .45-70's and such (and pistol calibers) sell so well at their prices is because there really is no other platform available for them. A .30 caliber, on the other hand, is available in virtually any configuration you can imagine. Don't get me wrong, as I would like to see the concept succeed. However, I will still remain skeptical as I don't see it doing as well as some would hope. I mean, at $500 you can buy a Browning BLR in proven cartridges, cartridges you can buy at virtually any sporting goods store.
I see the idea as a good concept, kind of like the Remington Ultra Mags, WSSM's, WSM's and such, but we see how well they are doing. I just do not see the American public running out to spend $500 on a Marlin lever gun in .30 caliber. Hopefully I will be wrong, but at this point it is hard to say. One only has to look back a decade or so and consider the .307 and .356 to get an idea on what has happened the last time this was tried...
Quick, my BLR in .308 is one of my favorite guns. Mine is an original Belgium gun, and was manufactured around 1970 or so. I mounted a Pentax 2-5x on it, and the gun loves 180gr Remington Core-Lokts! I have kept my eye open for one in .358, and will snap it up if the price is right.