Help identify my Converter

Without having it cut open to see what may or may not have been done to it, you can't tell anything. With the 1" wide ring gear, it is what we called in the converter industry an 11" converter. As far as the color goes, it means nothing, other than the fact it's been repainted at some time and might even be just a rattle can rebuild. I've seen my share of those.
I have my doubts about the "stall speed". I've yet to see a converter from a reputable high stall builder say that an 11" converter will give you much more than 2500-2800 stall and still work properly. For 2800-3500 usually you'll find a 10" converter used. For higher stalls we would go to a 9" or smaller converter depending on the customers engine/needs and end use. These converters are always custom made. Even some of the 10" units were custom built as we often built them for a specific use. Too many guys buy used converters thinking that they are high stalls, when in fact they are nothing but a stock converter. I was at a swap meet last summer and saw a converter for sale. The seller was claiming it was a 3500 stall conveter, but I knew differently. It was one of ours and our part number was still on it, along with the serial number we put on all high stalls. It was our part number 35-12SS, a modified GM TH350 converter we sold. We built those for about 300-500 rpm over stock (stock TH350 12" unit stalls at about 1400 rpm).
If this is a used converter, and you don't know the history of it, DON'T use it. As others have stated in many posts, a used converter makes a great door stop.