I have a john deere D140 riding mower for sale

I have a john deere d140 riding mower for sale. I bought it in 2018 from Home Depot. It’s in great condition with the exception of the engine. It not only leaks oil but appears to burn it as well. I’m thinking the engine will probably need to be replaced.  I’m selling for parts mostly but if you have the ability to fix or replace the engine then this might just be the diamond in the rough.  Asking 300.00