Lawrence (Mass.) Contributory Retirement System is searching for a manager to run $15 million to $20 million in an S&P 500 index portfolio. The $96 million pension fund will consider managers that run at least $500 million in S&P 500 assets and have three-year track records. RFPs must be submitted in writing only to Douglas W. Moseley, consultant at New England Pension Consultants, whose fax number is (617) 374-1313. Proposals are due by 4 p.m. EDT Sept. 19.