Looking for good low sodium recipes and/or cookbook

It's worth noting that most of the recipes you will encounter are oversalted, that being what we accustom ourselves to and what (along with fat and sugar) the food industry in general wants to accustom us to. You can simply reduce the salt you use, probably radically, and will soon find that you don't miss it- you may even find yourself disliking over salted food.

Honestly, I don't think you need specific recipes. What you need to do is look at the ingredients involved, and eliminate the salt some of those bring to it. You can do that by choosing products that are salt free, or starting with fresh ingredients. Some things, like mayo or such you may need to make from scratch, but use a salt substitute or one of the salt blends like Morton's Lite Salt. That product contains half sodium and half potassium salt, while tasting pretty much like regular table salt. I use it because my husband has high blood pressure, controlled with medication and diet. Lite Salt can be used exactly like regular salt as well, even in bread baking. I have opted to make many things myself, from scratch, just to control the salt content- to allow him to eat most of his favorite things. You can make your own mayo, salad dressing, mustard, even canned soup substitutes, broth, etc, and simply use a salt substitute instead of table salt. Some things, like soy sauce and lunch meats are more challenging. There are a few recipes on the web for soy sauce substitutes, and you can sometimes use small amounts of Bragg's Liquid Aminos. They don't use salt to make it, but it is made from soybeans which do contain sodium naturally. For a smoky taste, you can use Wright's brand, which also contains no salt. That's handy for making BBQ sauce, or adding a smoky element to thin sliced pork or other meat to make sort of a fake bacon. It's a bit of math to calculate the sodium per serving, but by making it yourself you can offer a wider range of foods that might otherwise be off limits. If he craves things like pickles- you can use a salt substitute, pickling spices and vinegar to make a quick pickle, because the salt isn't critical for preserving properties as it is for fermented type things like sauerkraut. There are plenty of make it yourself recipes on the internet, and you can make a lot more things yourself than you probably realize. I certainly was surprised, and happy to discover than in many cases, we actually liked the homemade product better- and it contained a lot less salt, and no preservatives or other things you really don't want in your food anyway. So it doesn't have to be about special recipes, just different ingredients, eliminating what you don't want and using what you decide is best.

Among sources you might look at crossovers between Jewish cooking (which, bc of the kosher laws, avoid seafood) and heart healthy recipes. One good one to search in libraries (out of print or very expensive) is heart smart cooking by Bonnie Stern. Another good one (current) is by Paula Shoyer.
Three good authors for Jewish (general) cookbooks are
* Joan Nathan (contributor here) esp on American, French and Israeli cooking
* late Gil Marks
* Claudia Roden.

I haven't read or cooked from it, but there is an American Heart Association Low Salt cookbook:
https://www.heart.org/en/healthy-living/healthy-eating/eat-smart/aha-cookbooks/aha-low-salt-cookbook-4th-edition

On the 4th edition so it must decent...