I have over 6+ years of reverse engineering experience, am very well-versed in x86/x64 assembly and consistently working with this kind of stuff, so I could get started on this right away.
While I cannot 'extract the source code' from the program, I can recreate it for you in either C++ or (preferably) C#. I can also provide detailed documentation for the code so it'll be easy for you or anyone else to understand what's going on and how it all works.
Upon completion, you will receive the full source code + documentation that was created from decompiling the program you speak of.
If you're interested in looking at my work, you can find me on GitHub @Fireboyd78. I'm very motivated to work with you on this project, especially since there's no protection or obfuscation on the executable. You may have a direct line of communication with me via Skype, Discord, or good old-fashioned e-mail.
Feel free to message me with more information on the project so we can discuss getting started on this as soon as possible. My work is 100% guaranteed to be exactly what you ask for, and I will provide free lifetime support for any bug fixes or serious issues that may occur.
Best of luck to you with your project!