State and Local Reservist First Responders Assistance Act of 2003

State and Local Reservist First Responders Assistance Act of 2003 - Authorizes the Secretary of Homeland Security to make grants to reimburse any State, local government, or Indian tribe for costs incurred as a result of a call or order to active duty of armed forces reserves who are first responder personnel, including: (1) costs of hiring first responder personnel to replace such reserves; and (2) overtime pay costs for other first responder personnel.

Permits: (1) reimbursement only if the State, local government, or tribe would not have incurred such costs but for the absence of first responder personnel; (2) costs to be reimbursed only for a reserve who serves at least six consecutive months on active duty at any time during the two years preceding the application for the grant; and (3) reimbursable costs to include any costs in connection with such reserve's active duty.