I never try using tar to restore on Windows before but looking at the article from VERITAS regarding tar restoration based on solaris...
I belive it still possible on Window. Try download GNU tar and mt command,
use robtest command to move tape to drive and proceed restore. The thing to take note is the block size. In windows, the default block size used is 64.
However, this is just a suggestion from me and i never try it before so i suggest you do a test run first. Hope this helps