SINGAPORE (Reuters) - Oil prices pushed above $49 a barrel on Monday, approaching record levels as worries about the stability of supplies from Iraq, Nigeria and Russia compounded concerns over low fuel stocks ahead of winter. U.S. light crude climbed to a session high at $49.36 a barrel, up 48 cents and just 4 cents below the all-time intraday peak set in late August at $49.40. At 10:38 p.m. EDT Sunday, U.S. oil was 32 cents higher at $49.20. Oil was driven higher last week by a big dip in U.S. oil stockpiles, at a time when inventories should be...