skeet,
I've ben very pleased with Weatherby's rifles. I have a couple now but they are the more modern Mark V Accumarks. The older wood stocked versions were a real peach to look at and I think they were known to shoot very well but of course they were expensive. The only thing I balk at are their proprietary cartridges like you're looking at now. The odd ball calibers like the 338 Weatherby sell for over $90 bucks a box!

I think that .300 Weatherby Mag might be available in factory loads other than Weatherby's loads.
I know nothing about the glass.
I would think that gun was worth $600 even without the glass.
On a side note that doesn't mean a darned thing, Weatherby's current plant is nearly in my backyard here on the central coast of California. Also, my Dad bought a go-kart from Roy Weatherby for my brothers back in the '60's. It was in the front window of his old shop in South Gate, CA!

I've been meaning to go in and ask the sons who now run the corporation if they remember that old cart as it was theirs as young kids!