It comes in two size - the Grand Madison and the Small Madison. I bought mine from Amber at Chic and Saavy Crafter (She is active here on SCS)
Poppy Stamps Grand Madison Window Die **Ships Free!**
Technically it is made by Poppy Stamps which i think I read somewhere on SCS is an subsidiary of Memory Box, so search on both names if you aren't having luck. Amber does free shipping on dies and clear stamps, and ships so fast - I had mine in two days. Darn you! I just went to her site to see if it was in stock and saw lots of things I want.