Chipped beef is supposed to be rinsed. At least according to the labels on the brands in my area.
Under warm running water, separate the slices a bit and let the water run through. Doesn't take long to cut the salt by a large portion. If you soaked it a long time, it wouldn't have any flavor left
I too am on a sodium restriction and enjoy SOS every other month or so. Other tricks to a lower sodium SOS. Use a full fat milk, they're lower sodium (sodium is water soluble, so the more fat in the milk, the less room there is for sodium). Be sure and start with some chopped onion, a couple of tablespoons, and maybe a tiny bit of garlic, 1/8 teaspoon. Build the roux from unsalted butter/olive oil/grapeseed oil right in the pan with the onions. Season with some hot sauce and pepper and a squeeze of lemon at the end. YOu shouldn't need any salt.
Any of the salt free herbal mixes can be added to taste, Frontier, Mrs. Dash and so on.
Commercial bread is prettty high sodium too and biscuits are often worse. Pick your starch carefully. If your restriction is really tight, maybe some baked or roasted potato would be better than bread.
thymeless