Banks are getting ready to sell billions of dollars in debt borrowed by Elon Musk’s X, bringing Wall Street a step closer to exiting the nerve-racking deal that financed the social-media company’s buyout. Morgan Stanley bankers have reached out to investors ahead of a planned sale next week of up to $3 billion of debt the bank and others such as Bank of America and Barclays lent to complete Musk’s 2022 buyout of the company then known as Twitter, people familiar with the matter said. The price Musk paid for Twitter was high, even at the time of his purchase, and the company’s rocky performance had knocked down the value.