Here is a good design, and I like the tool free removable legs design.
http://users.tpg.com.au/users/daveg/gem6/gem6.html
Dave is a member here so perhaps he can jump in and advise what might be the cost for a CNC shop to make one of these.
A nice addition would be a Rotating plate to give more freedom in Az polar alignment.
This is the one I would like though
http://www.pier-tech.com/tri-pier_2_...stimonials.htm
But doing some research i found this article.
http://www.dd1us.de/Downloads/A%20te...cope%200v4.pdf
Which led me to a Company called LINAK. The make various types of Linear Actuators. And there Deskline D2 and there Lift Column L2 series are i think the basis of the Pier-Tech design. The facility to adjust the height without affecting polar alignment is a good feature to have.
You can buy the Liner Actuators relatively cheaply and make incorporate it into a pier design. That is what I think Pier-Tech have done but they are quiet expensive i think for what they are.
Regards
Fahim