The Soviet Union may be moving toward a free market, but it may be a long time before the phone system catches up. Mark Ganslaw, president of Silver Spring-based Data Sciences Inc., sees a business opportunity in that -- at least for a while.

Ganslaw founded East-West Express, through which people here can send facsimiles to Moscow, where the machines are scarce, from their own fax machines. Ganslaw gives the sender the phone number and access code to the Moscow office of a Soviet agency called PolyFax, where fax recipients are called to pick up their documents. Soviets who don't have their own fax machines can use PolyFax to send documents to the United States.

The service isn't cheap: It costs $25 to $35 to send a four-page fax to Moscow, depending on how often the sender uses the service. That's because it's been an expensive venture, Ganslaw said. He provided PolyFax with two fax machines ("if one broke, they wouldn't be able to fix it") and sends the fax paper over, too.

He doesn't plan on East-West Express being around too long. "Two or three years from now, everyone in Moscow will have fax machines, too," he said.