July 10 (Reuters) - Saudi state oil giant Aramco started selling three-part bonds maturing in 10, 30 and 40 years, fixed-income news service IFR reported on Wednesday. Aramco has placed the initial guidance around 140 basis points (bps) over U.S. Treasuries (UST) for the 10-year bond, 180 bps over UST for the 30-year, and 195 bps for the 40-year, IFR said. (Reporting by Shamsuddin Mohd, Editing by Louise Heavens)