need fuel tank for small engine mower model 20107 or suggestion on how to seal seam?

The gas receptacle on the mower is opening at a seam . I don't see a fuel tank on the internet toro parts lists so in the alternative does anyone know what I could use to reseal the seam? the tank seems to be made of a plastic like substance. Usually I turn to JB weld for repairs but I don't know if it will bond with plastic. Any help with finding a tank or repair solution? Thanks for any insights.
Kspence