At the end of the comments on that pic, someone mentions that the original was lost in the great Tumblr purge. I probably have the original somewhere. If so, it's buried DEEP in my archive and I don't have the time to dig for it right now :/
Going as far as spending actual time into replacing the logo for yourself, on a page you spend less then 1 second on per visit (or none if you fav'ed post/list) is pretty obsessive. But whatever floats your boat, you're welcome