I've seen those ($200-$500), and there's still a few good stock pieces in the yards around here but I needed it addressed immediately and for free. The welder handles material that thick though I haven't welded in some time, and I did the best I could to clean everything and drilled holes to relieve stress and prevent future cracking. A 90° attachment was necessary for the tops but I had direct access to the front by the drag link, though I broke a step bit after relaxing my arm at the wrong time. Since I found the cracks after using brake cleaner I employed soap/water/alcohol to clean the residue, waited a day, and utilized a Coleman torch to hopefully burn away anything that was left. I opened all the doors, used multiple fans, and constantly utilized compressed air to avoid breathing any possible phosgene gas. I know grinding on welds weakens them and is frowned upon but it needs to look decent and not like a dumpster fire. I was unable to grind the cracks into a "V" prior to welding which is also unfortunate.I see you filled them..
There are companies out that make drop in new ones out of 3/16" steel that fix a lot of the OEM issues
I'd love to pull the engine and replace the cradle but that's an impossible dream at this juncture and I've already let things start getting more involved than originally planned. Short of replacement I'd prefer to at least remove it and clean/weld it better but that's just not possible right now either.