So based on some reports the
Huawei SmaKit S7: http://www.pocketables.net/2010/05/h...ndroid-21.html
supports UMTS 2100 (3G), as well as 900/1800 (2G). Still trying to get some confirmation on that. http://www.expansys.com/d.aspx?i=199911
http://www.expansys.com/ft.aspx?k=123978
This is more expensive then your current tablet though.

Also the Dell Streak on O2 supports those bands but as of now it's locked to them.
http://www.wirefresh.com/dell-streak...ontract-in-uk/
Plus it's only 5" (though there are rumours of a 7" and 10" version)

Watch out for devices like the SmartQ-V7 http://en.smartdevices.com.cn/Produc...912/04-40.html because they don't actually have on-board 3G (instead it's Bring-Your-Own-USB-3G-Modem).