I finally found a source:

Bearberry Creek Water Gardens
RR2
Sundre, Alberta
T0M 1X0
Canada

Phone: +1 (403) 638-4231


Jeff Frontz wrote:
I'm looking for a source (seed, nursery-propagated tuber, or
nursery-propagated plant) for Sagittaria cuneata Sheldon. I've found
several online for S. latifolia, but none for S. Cuneata Sheldon.

Thanks,
Jeff