I’d like to back up Vaughan’s suggestions. I’d be inclined to avoid Horning as the river there can be incredibly busy with motor cruisers, day boats and the large trip boat ‘Southern Comfort’.
Weyford Bridge Inn is located toward the top of the river Ant, and as the Weyford Bridge is quite low, quite a lot of motor cruisers can’t get under it, so it’s lovely and quiet on the river above the bridge. There is also a stretch of disused canal that cruisers are not allowed to use but canoes can, so that would be ideal.
The stretch of river up at Coltishall is also quiet. That’s the head of navigation for motor cruisers on the River Bure, but canoes can go further up the river. You just have to carry your canoe a short way to the other side of the lock.
If I was planning a canoeing outing I’d certainly opt for Weyford Bridge or Coltishall. The Ranworth and Sutton accommodations that CambridgeCabby has suggested are certainly good alternatives, but I don’t think the canoeing would be as good.
You might also consider staying somewhere in Beccles, where there’s probably a bigger choice of accommodation. You can use the slipway near the yacht station to launch your canoe, and there is parking not too far away. The river between Beccles and Geldeston is very popular with canoeists and paddle boarders as it’s fairly quiet.