Windows XP Tablet edition isn't available as retail but is available as Microsoft OEM version. As with all the big brands the restore disk is based off an image with all drivers and software pre-loaded. The actual Windows component will be the same.

FWIW the current, active, Windows XP Tablet Edition OEM SKU is K46-00105.

1998.5 T-Red on Midnight Blue SVT Build Number 5320 of 6535