OVERSEAS buying pushed the Hang Seng Index up 125.12 points to close at a record high of 7,676.22 last Thursday despite gloom over Hong Kong's political future. The buying spree followed a significant re-rating of Hong Kong stocks by Morgan Stanley International's respected analyst Barton Biggs. He recommended the weighting of Hong Kong stocks within the financial house's global equity portfolio be raised to three per cent from two per cent. Across-the-board institutional buying gave the market a robust turnover of $4.05 billion, compared with daily turnover of about $2 billion over the previous days. Whether the rally will last still hinges on the outcome of the meeting of the foreign ministers of China and Britain in New York this weekend. Brokers believe any positive signs from the talks could send the index to new heights. However, a continuing war of words between the two sides will keep the market sentiment from firming and ensure turnover is weak, brokers say. The week's first three trading days saw featureless trading with few shares changing hands. Investors stayed on the sidelines on Monday, with the index losing 72.96 points to close at 7,452.09. Henderson Land was the best performer, rising $1.50 to $22.70 per share after reporting a 64.4 per cent rise in net profit to $4 billion for 1993. Cautious sentiment continued to dominate the market for Tuesday and Wednesday, with the index edging up 18.41 and 80.6 points respectively. Trading remained thin on a modest turnover of $2.12 billion and $2.49 billion for the two days. Property and utility stocks benefitted most from last Thursday's rebound. New World Development gained 80 cents to $20.80 on turnover of $119 million, while Sun Hung Kai Properties rose $1.25 to $40.75. Analysts believe that investors began to re-gain confidence in the property stocks, which have long been plagued by negative news about mortgage tightening by Hong Kong banks. Hopewell was heavily traded for the week. Its shares rose from $5.40 on Monday to close at $6.05 on Thursday.