PRETORIA, OCT. 22 -- South Africa's state-owned weapons industry, virtually nonexistent before the United Nations imposed an arms embargo 11 years ago, has rushed into the international export market, unveiling a new armored vehicle in an effort to beat a competing model that is expected to be introduced by Italy in about two weeks.

Pretoria hopes the highly mobile search-and-destroy fighting machine will place South Africa higher among the world's top 10 arms exporters. In 1977, South Africa imported about 70 percent of its armaments, compared to only about 5 percent today.

The Rooikat, named after a small but deadly African lynx, was demonstrated to local and foreign journalists yesterday at a weapons proving grounds here by the South African Army and the state-run Armaments Corp. of South Africa, known as Armscor.

At a separate, public exhibition of the Rooikat in nearby Kempton Park, Defense Minister Magnus Malan, who is a director of the normally secretive Armscor, touted the eight-wheeled vehicle as "unique, the only one of its kind in the world . . . it stands back for no one and nothing."

Introduction of the Rooikat, which is mounted with a 76-mm gun, follows Armscor's highly publicized success in the Angolan war with the G6, a 155-mm long-range howitzer that is the only wheeled, self-propelled artillery weapon outside the Warsaw Pact countries.

One of Armscor's principal marketing pitches in its brochures and at international arms exhibitions is that most of its nearly 4,000 products are "battlefield-proven."

The G6 and its towed predecessor, the G5, were credited by foreign military analysts with turning the tide in southern Angola earlier this year and preventing Angolan and Cuban forces from overrunning anticommunist guerrillas of Jonas Savimbi's National Union for the Total Independence of Angola (UNITA).

Armscor officials said the Rooikat, which went onto the drawing boards in 1984, was never used in the Angolan war. Pretoria's involvement in the conflict ended in September with a cease-fire and troop pullout.

Armscor, which reportedly earned less than $10 million as recently as 1982, has become South Africa's largest manufacturing export earner, with sales this year expected to top 3 billion rand, or $1.25 million at the current exchange rate. Only gold and coal exceed its export earnings.

Armscor refuses to identify countries to which it sells its weapons, but its executive general manager, Johan van Vuuren, confirmed reports of 32 worldwide clients, and estimated that the Rooikat would add 10 to 12 percent to the company's sales. It will go into production early next year and become operational in the South African Army in late 1989, he said.

Jane's Defense Weekly has said that Armscor's primary market is in the Third World, including countries in the Middle East and Latin America. Armscor recently displayed sophisticated air-to-air missile systems at a military exhibition in Chile, and although officials in Pretoria deny it, it has been linked to arms sales to contra rebels in Nicaragua.

South Africa has also denied persistent reports that it has delivered up to 340,000 rounds of G5 cannon ammunition to Iran through a Dutch intermediary. When asked yesterday about similar reports that it was selling ammunition to Iraq, van Vuuren refused to comment, saying: "We don't disclose our markets."

He said that South Africa "has enough trouble as it is" finding export markets without publicizing the identities of its clients.

Armscor also produces these weapons: the South African Army's own R4 assault rifle, a copy of the Israeli Galill rifle; rocket launchers; modified Puma helicopter gunships; armored personnel carriers; small warships; and the Cheetah, a combat aircraft based on the French Mirage and Israeli Kfir.

It employs an estimated 23,000 people, while providing jobs for tens of thousands more in more than 900 private companies that make components for Armscor products.

The Rooikat, which in Afrikaans means "red cat," is advertised as a fast and highly maneuverable vehicle designed, according to van Vuuren, to "seek and destroy deep in enemy territory."

With a crew of four men -- commander, driver, gunner and loader -- it has an operating range of 620 miles at speeds of 75 miles per hour on paved roads, and can travel cross-country at 37 mph, its eight-wheel drive powering it up gradients of up to 70 percent.

Lt. Gen. Andreas (Kat) Liebenberg, chief of the Army, said at a press conference that the Rooikat would be pushed into service because it can outmaneuver and attack tanks in battle conditions common to southern Africa, where engagements often are at close quarters.

In a demonstration, the low-profile vehicle was difficult to detect as it sped out of the bush toward a test track and skidded to a stop a few yards in front of observers before turning sharply and disappearing again into the hills.

Because it has a stabilized turret, Armscor officials said, the Rooikat can fire rapid rounds from its 76-mm computer-assisted gun while moving over rough terrain, hitting tanks at a range of 1.25 miles.

Armscor officials refused to disclose the Rooikat's cost or sale price. Van Vuuren said Armscor had not planned to unveil the Rooikat now, but changed its mind when it learned that "one competitor was ready to make a move."