Keep trying this guy. I bought an LED light source from him a few years ago. He makes them in small batches and waits till the batch sells out before making another. He took a while to respond to my e-mails. I believe you will hear from him eventually<g>, but I think this is a labor of love for him and not a business.
My LED works great and my SEI works although I really don't use it in the field, I bought it on eBay out of curiosity and the desire to own a part of photographic history. When I got it, it was setup to hold the really old batteries wrapped in paper. The LED replaces all that and the hard to find bulb and it works great. I think I paid forty bucks for it.
Hang in there and he'll respond.
-R