It is good to hear that your weight is at least stabilized, I was wondering if you were still losing weight or not.
I kinda wish I was having your problem at the moment LOL. Since I couldnt get the topamax anymore I have gained back all the weight I had lost, and then some hahahaha. The topamax took me down to 194 lbs, havent been that light in years, but now I have ballooned back up to 235.
My wife said she couldnt get her arms around me anymore, even though she had a difficult time even when I was considered smaller hahahahaha!
The weight lifter powder would help you put on some mass, but you would have to keep using it to keep the effect. Jose had the right idea with the shakes, but it wouldnt hurt to slip some of the powder into the shakes to beef you up.
Back in my power lifting days when I needed to bulk up. Instead of using the HGH, roids, or powders, I would eat like a mad dog. I mean stuff myself constantly. I would order a large pizza with all the toppings and eat the whole thing, and have a half gallon of ice cream for desert. Proteins are your friend when your trying to gain weight, and that would help if your low on iron too.
I know you wont be able to eat that much, but maybe you might be able to bench press your son when he ****** you off LOL.
Good luck on that bro, and will be keeping you in my prayers.