Here’s the link to the Vixen Optics USA Polarie page:
http://www.vixenoptics.com/mounts/polarie.html
Here is a link to a Kenko unit from Hutech in the USA.
http://www.sciencecenter.net/hutech/...memo/index.htm
Another unit is the Astrotrac here
http://www.astrotrac.com/Default.aspx?p=how-it-works
The Losmandy star lapse system is here
http://www.losmandy.com/starlapse.html
There is quite a range in prices and size/weight between the above units.
Cheers
Dennis