I don't have any experience with the amps you are looking at, but the middle one (morgan jones) has the best reputation. There are also later derivations of that design.
Do you have experience with tube amps, or tube gear in general? A standard tube amp generates lethal voltages, so it is not a project to be treated lightly. For headphones, there are low voltage options available, that are safer.
If you are comfortable with the voltages, also a question of budget, and how much work you want to do.
There are places like this
http://glassjaraudio.com/that sell pwbs or kits
Another place to look at amps is here
http://www.cavalliaudio.com/diy.htmlRandy