I broke a blade once and I was in a pinch. I took a blade into the hardware store with me (doitbest) and matched it to an MTD blade size, but I did have to ream out the center hole to size. I bought 3 so they would all match. The mulching bends/flutes in it was different places than the MAH60 mower blade and was thinner metal. They worked ok, but they dulled fast. And when I hit thick turf, I had to really slow down to keep the inertia of the blades up. Took them off last season and put on a new OEM blade and sharpened the other two originals I had. I now have 2 sets and just swap blades to sharpen at my convenience.
I will be interested if you find an alternate thicker blade with the right flutes. My mower blades get a lot of use.