This is the list I personally used when I was getting into Theory but for the Political Economy section the Soviet Political Economy textbook I found to be very good
https://www.marxists.org/subject/economy/authors/pe/index.htm
Edit: also the book 'fundamentals of marxism-leninism' is a pretty good book but I have found it to be littered with traces of Kruschevite revisonism
PDF:
https://www.google.com/url?sa=t&source=web&rct=j&url=https://www.redstarpublishers.org/FundamentalsML.pdf&ved=2ahUKEwja8o_vjuXqAhVxlXIEHQJqDfoQFjALegQIAxAB&usg=AOvVaw1mjfmrfCuaf1sxnCXrp_KX
This is the list I personally used when I was getting into Theory but for the Political Economy section the Soviet Political Economy textbook I found to be very good
https://www.marxists.org/subject/economy/authors/pe/index.htm
Edit: also the book 'fundamentals of marxism-leninism' is a pretty good book but I have found it to be littered with traces of Kruschevite revisonism
PDF:
https://www.google.com/url?sa=t&source=web&rct=j&url=https://www.redstarpublishers.org/FundamentalsML.pdf&ved=2ahUKEwja8o_vjuXqAhVxlXIEHQJqDfoQFjALegQIAxAB&usg=AOvVaw1mjfmrfCuaf1sxnCXrp_KX