OSA-class I Polish missile craft

[aukepalmhof]

For the 30th anniversary of the Polish People’s Army, the Polish post issued a set of stamps of which one shows us a fast attack missile craft of the OSA I type. Which is depict is not sure

Built-in Russia and 13 units were transferred to the Polish Navy in the 1960's.
Displacement: 171.5 ton standard, 209 ton full load , dim. 38.5 x 7.6 x 2.5m.
Powered by three M503G diesel engines each driving its own propeller shaft, each 4,000 hp., speed 40 knots.
Armament 4 - SS-N-2B Styx missiles launchers, 2 - II-30 mm AA-230.
Crew 28.

With the introduction of Russia's Osa and Komar missile craft, nations with small navies saw immediately that there was a lethal new addition to sea power which altered the balance of naval conflict to their advantage for the future. Small missile-firing attack craft of this type would enable them to wage a war at sea against larger and superior forces at a minimum cost. Osa's of the India Navy proved the potential of these craft during the war against Pakistan in 1971-1972. In an attack on the shipping of Karachi on the night of 4-5 December 1971, they sank the 2.325 ton destroyer PNS "KHAIBAR", damaged her sister craft, the "BADR", and hit the "MUHAFIZ" coastal minesweeper. On the night of 8-9 December, they sank one British and one Panamanian freighter and damaged a Pakistani naval tanker and shore installation.
Most of this craft were armed with Styx missiles. Before the Styx missile homing system can acquire the target, Osa-class boats must maintain a straight heading for five minutes before launching the missile. Since in moderate to rough seas they would find it difficult if not impossible to follow a straight course for such a period, launching can only take place in smooth to moderate sea conditions or from a sheltered location.
As a Styx missile approaches its target, its terminal homing seeker takes over. Providing the target is equipped with an electronic countermeasure system to detect the approaching missile, steps can be taken to jam it. In the 'Yom Kippur' war of 1973, the Israelis claim to have successfully employed 'Chaff"- clouds of small aluminum strips dispersed by grenades in the path of the oncoming Styx to provide decoy targets
The concept is similar to that of Window, employed by Allied bombers to baffle German radar operators in World War II

Chaff grenades are generally tried in groups. In the case of fast patrol craft, nine will provide a chaff cloud of sufficient echoing area and intensity to protect a craft of 0 ts displacements. The idea is that the missile's radar seeker locks on to and tracks the chaff cloud (in the case of missiles known to employ infra-red seekers, flares are used to provide a decoy) instead of the vessel.
The Osa was the first Soviet fast patrol boat with a steel hull. Like the similar but smaller Komar, its lines are dominated by four large hooded Styx missile launchers mounted in this case in two pairs abreast of the deckhouse. Two variants are in service - Osa I, with slab-sided launchers and the more recent Osa II with cylindrical, elongated dustbin shaped launchers.
Sixty-five Osa Is are in service with the Soviet Navy and fifty-five Osa IIs. In fact, the Osa is the world's most widely used missile craft. Apart from 120 delivered to the Soviet Navy by mid-1978, a further 160 have been transferred to other navies as follows. Algeria 3, Bulgaria 3, China 60, Cuba 5, Egypt 6, Finland 6, East Germany 12, India 8, Iraq 10, North Korea 8, Poland 12, Romania 5, Somalia 3, Syria 6, Yugoslavia 10.

Copied from the book Naval Fast Strike Craft and Patrol Boats by Roy McLeavy.

Stanley Gibbon gives for the Polish stamp the name "PUCK", but I believe one of the Osa I class is depicted.
All of these Polish vessels have been decommissioned between 1984-2006.

https://en.wikipedia.org/wiki/Osa-class_missile_boat
Poland 1973 1z50 SG 2263, scott?