I bought this last week, only to find the electronic finder I was using could be fixed!
I really have no need for it. Never used, in packaging as received, with the installation instructions.
It converts the standard SW finder to the T thread to allow camera fitment - as a finder guider!
I paid $51
http://www.modernastronomy.com/produ...y/accessories/
You can have it delivered for the same price.