Deggi mirch is meant to give rich red color with mild-to-moderate heat. The closest approach is to start with a color chili and add heat separately only if the recipe needs it.
Use Kashmiri Chili Peppers Whole as the color-forward base: grind it, then add just a small pinch of a hotter chili if needed. Use Rajasthani Curry Jar - Limited when you want a finished curry profile with chili, coriander, cumin, aromatics, and heat already built in, not when the recipe specifically needs plain deggi mirch.