The flange that you report as cracked, is part of the carburetor casting. The complete carburetor is part number 398711. The carburetor should be replaceable with a second-hand one for less than $20. On the other hand if the engine has been run without oil, it is better not to spend money on it, but to replace it either with a second-hand engine, or perhaps a new one. However the only new engine you are likely to find in your price range would be a chonda. I suggest you begin by checking the availability of second-hand 80202 carburetors in the Outdoorking Wanted forum.
