I don't know what half speed means, I just copied it from the site, I suppose I could look it up. Something to do with the groovy grooves I suppose. There is a clear vinyl version of the same title I still need to order.
My father used to work in the Oldbru brewery many, many years ago (I'm guessing in the 1930s) and that's one of two surviving empty bottles we have (my brother has the other). The label is extremely fragile. I think it's (hic!) worth a lot of money, maybe as high as $32.98. In my entire life I've maybe drunk a half a bottle of beer. Never liked the stuff.