re: Where can I buy this mold?

I think it’s a Wilton mold
https://nl.aliexpress.com/item/2014-new-rectangle-100-foodgrade-3d-silicone-cake-mold-cake-decorating-fondant-mould/1681585498.html?spm=a2g0z.search0301.4.87.zExNJv
I hope for you it is this one