Try Camping World (1-800-626-5944, US & Canada).  Thetford 135 - 
$59.97, 235 - $99, 265 - $124, and "electric" - $149.  All prices US 
dollars.  There is a retail store in NJ, and several others scattered 
throughout the states if you don't want to do mailorder and pay 
customs.  More geared to the RV/Motorhome types, but many items of 
interest to others as well.  Haven't ordered from them yet, so can't 
advise as to how their customer service is.  If the turnaround time 
between when I called and when I received the catalog is any indication 
(4 days), it's pretty good.  Good Luck!

Scott
'84 Westfalia (122,000mi)