PointCast Inc. said it will unveil a new subscription service for business customers and partner with Visa International and Barnes & Noble book retailer to expand its revenue sources and set the foundation for electronic commerce. The closely held Sunnyvale-based company that broadcasts information directly to personal computers said it will offer a wider array of news through its Companies Premier service, which will feature financial information from First Call, Hoover's and Reuters Securities News. PointCast will charge subscribers a fee for Companies Premier, although pricing won't be announced until the first quarter of 1998, when the expanded news service debuts. PointCast already offers a free news service. PointCast also said it will provide links to Barnes & Noble. In addition, PointCast said Visa International will be its preferred payment method.