I used to work for an industrial safety company and we had them made to give away at a trade show several years ago. If anyone is interested, I could post a close up picture and I'm sure you could get one made up at Kinko's or something.
I'm not sure if 8 points is something to worry about. I'm sure there's more knowledgeable folks here who could help more, but me personally I wouldn't worry about it. My first two AG batches, I missed my OG by 15-20 points!!! The beer still turned out really good. However, I might have left it...
It's most likely a little 'green' still. 4 weeks for a stout is really pushing it. I'd give it another week or two and everything should mellow out. Usually, when I do a sout, it's two months minimum before I even think about drinking it. And at this point, I'd keep it cooler than fermentation...