I've never looked at the Canon, but I'm pretty certain at a minimum all the L glass is WR (which in itself is more than Pentax has)
A little looking comes up with this list of verified ones. nothing in the close to affordable range though and only FF lenses (no EF-s)
EF 14mm f/2.8L II (True)
EF 16-35mm f/2.8L (True)
EF 17-40mm f/4L (True)
EF 24-70mm f/2.8L (True)
EF 24-105mm f/4L IS USM (True)
EF 70-200mm f/2.8L IS (True)
EF 70-200mm f/4L IS (True)
EF 300mm f/2.8L IS (True)
EF 400mm f/2.8L IS (True)
EF 500mm f/4L IS (True)
EF 600mm f/4L IS (True)