Here are some cabs that will work with the Stock ROM:
Bckgrnd 4 all Tabs.cab
Clear Weather Background (with line).cab
Email Tab 2.5.cab
With the Bckgrnd 4 All Tabs cab the calendar tab will be transparent; however, you will want to install the Clear Weather Background cab or your weather tab will look odd. The Email Tab 2.5 makes your email tab look more like the Sense 2.5 tab, i.e. you will see an image of the entire email instead of the envelope.