LJCF - 8/4/2020 13:17

Where is your source of heirloom seeds? In particular for a soft white wheat, which I understand is the choice for authentic Italian pastas when very finely ground.

Soft white wheat is a low protein wheat and a lot of it is grown in the Pacific NW in the Palouse region and most of this wheat is exported to Asia for use in making cookies and noodles.
White wheats are hard to grow because of a head sprouting problem if the grain gets wet when it is ripe which quickly adds a big dock and makes it hard to sell. Or pig feed.
As mentioned Durum wheat is traditionally used to make pasta. Hard white wheat works well for making whole wheat breads that don't have the the problems that you have using whole red wheat flour.

If you have a food Coop in your area or in a college town nearby you can usually find all different kinds of wheat available for sale for home use and grinding or I suspect Google.com will find a source for you.