I too have reinvested time and energy into boosting my immune health. I've taken a multi-strain probiotic supplement and am considering colostrum as well to jumpstart my energy level. I do not know of any ways to get lactoferrin from a non-milk source. The one I've found is a sub-fraction of whey, and is an iron-binding glycoprotein. It is available only through doctors, brand name Sedona Labs Pro.
I have been exploring a new product by the makers of my probiotic. It is also a multi-probiotic supplement, called Flora Sinus, with added NAC (N-Acetyl-Cysteine), which is a natural antioxidant and precursor for Glutathione, considered the body's most powerful antioxidant, for boosting immunity. You can check it out at www.nutri-health.com.
Healthy, strong immunity to all!