USSR SOVIET RUSSIAN PIN BADGE LENIN HAMMER AND SICKLE

Description

USSR SOVIET RUSSIAN PIN BADGE LENIN HAMMER AND SICKLE. Condition is "Used". Shipped with USPS First Class.
I don’t know anything about these really. Picked them up at an estate sale of a woman from Russia. Labor party medal? Souvenir?
The large one in the center is 2 3/4” x 1 5/8”. The top piece has Lenin profile, hammer sickle and a red star, red star with banner and another red star inside a wreath with banner. Have no idea what the banners say. The bottom piece is 5-point star shaped with a helicopter and stars inside. A commemorative of some sort? The back reads: B.4. 36978 1991 r.
The small round pin is approx 7/8”. The perimeter is encircled with cerulean letters - can’t translate, 5 colored circles with XII in the middle, dove with olive branch, symbol of peace and what looks like MOCKBA (looked it up, and translates to MOSCOW) under the dove. The back says U45K.
The rectangular pin (1 1/4” x 1 1/8”) is an empire style building with Russian letters and the years 1806-1808. I don’t know what building this is. Might be a cathedral or museum or government building.