Is catur vyuha of Vishnu mentioned in puranas and Mahabharata?
Yes, chatur vyuhas are mentioned in Mahabharata: Santi Parva:
He who is the eternal Supreme Soul and is known by the name of Vasudeva. ... There is nothing among mobile and immobile things in the universe that is immutable, except Vasudeva, the eternal Purusha. ... That illustrious one, viz., Vasudeva, who is called Kshetrajna, and who is freed from attributes, should, O king of kings, be known as the puissant Sankarshana, when he takes birth as Jiva. 2 From Sankarshana arises Pradyumna who is called 'He that is born as Mind.' From Pradyumna is He who is Aniruddha. ... From Aniruddha springs Brahma. The latter takes birth from Aniruddha's navel.