I'd be thrilled to see a modern made Howe/Whelen sight complete and finished with micrometer windage and elevation. I'd be even more impressed to see one that was somewhere approaching financial viability. An "Improved" version I can't imagine??
I'd say, this is a wonderful opportunity to buy one and I expect this one will bring a substantial sum, but considerably less than it would cost a professional to manufacture.
Best to begin with the book, considered a standard text for those interested in quality gun work, I believe much easier to come by and considerably less expensive than the sight.
here's a free download
http://www.milsurps.com/showthread.php?t=27137You will have to look up the sight on your own...