Bill Ward of Black Sabbath used this exact Ludwig Standard snare for years. Just search for "Black Sabbath Paris 1970" on YouTube.
The Standard is basically an Acrolite minus the bead in the shell. It's a seamless, spun aluminum shell. Except for a few high-end boutique builders, spun shells aren't really made anymore these days. I believe even the current Ludwig Black Beauty, Acro and Supra shells aren't spun like their predecessors.
Apart from 1/2" difference in the depth of the shell, the Standard is basically identical to the current 5.5"x14" George Way Aero by Dunnett, which costs $500 in the US.
The absence of the bead in the shell eliminates distortion in the resonance of the shell. That's why it sounds fatter, deeper and rounder, vs. an Acrolite, which has more bite, but far less "meat". I personally find that only snare shells of 5.5" deep and up could/should have a bead (though I prefer beadless over beaded metal shells altogether). I never liked Acros, unless you crank it to somewhere super-funky. Bit of a one-trick pony. The Standard, however, goes wherever you take it. Fat and low, or super funky, and anywhere in between. A total must-have for any session guy. I do recommend upgrading the stock 1.6mm hoops to 2.3mm hoops. Adds crack and focus, without affecting any of the wonderful low end or tone.
I scored mine on eBay for $51. A 1969 in near mint condition. I don't know why no one else was bidding but I was a happy camper. They pop up on eBay regularly for between $150 and $200. Even at $200, it's worth every penny.
Only thing to watch out for are the lugs. The lugs are fitted on the shell with proprietary Ludwig fasteners/nuts inside the shell that are sort of like rivets. They are popped on once by a machine but if they come loose, you can't refit them. The lugs do also have regular (but raised) screw receiving holes. If a lug comes loose, just discard the nuts and get some raised washers with regular lug screws (like this one: http://drumsonsale.com/media/catalog/product/cache/1/image/750x750/9df78eab33525d08d6e5fb8d27136e95/C/W/CW-05N.jpg).