Thank you, Fabrizio, for all your comments!
Замечательная композиция! :)
Раньше поселок Озерки так и назывался - Сейвясто.
Озеро Ушаковское was Tervajärvi ("Смоляное озеро")
I do not know for sure, but I think, that the symbol looks like a municipal coat of arms. Actually in Finland the rural municipalieties did not have arms of coats like the cities had.
However during the 1950'sthe rural municipalities started to get ones just like boroughs.
As for the territories, which were transferred to the Soviet union in 1944 (Moscow Armistice) and congfirmed in 1947 (Paris peace treauty), therre were no coat of arms for the rural municipalities.
Because of that some cultural societies started to make coat of arms as if they had officially existed.
So I would guess, that that coat of arms has been made afterwards as a symbol of the past municipality or the past Evangelical Lutheran parish.
The Evangelical Lutheran parishes were also the secular local government until 1865/1866.
Бусловка was in Finnish Sarvijoki (Horn river).
Спасибо. По Вашей ссылке речь о крепостной пушке, а согласно документам по Выборгской крепости батарея №5 имела на вооружении батарейные пушки. Калибр у них один, но пушки разные.