Nov 10 (Reuters) - FTX is scrambling to raise about $9.4 billion from investors and rivals, a source said on Thursday, as Chief Executive Sam Bankman-Fried urgently seeks to save the cryptocurrency exchange that has been buffeted by a rush of customer withdrawals.Bankman-Fried has discussed raising $1 billion each from Justin Sun, the founder of crypto token Tron, rival exchange OKX and stablecoin platform Tether, according to the source who has direct knowledge of the matter.Earlier on Thursday, however, OKX told Reuters it had been approached this week by Bankman-Fried, who described liabilities of $7 billion that needed covering fast.Bankman-Fried also said his trading firm Alameda Research, which sources have said was partly behind FTX's problems, was winding down trading.Users rushed to withdraw $6 billion in crypto tokens from FTX within days, after a news report earlier this month raised questions about Alameda's balance sheet and Binance CEO Changpeng “CZ” Zhao tweeted that his firm would sell its entire share in FTT, which gives holders discounts on FTX trading fees."