A possible Chetverikov MDR-6?
Both reports are from Finnish National Archives Service (Kansallisarkisto).
Ps. I can help you to find a specific combat report, if needed, from the Finnish Archives. All the c. 3000 - 4000 reports made during the Winter War and Continuation War are there. Just send a PM.
1. Date: 26.7.43. 15.10 - 16.10.
2. Area and altitude: 5 km SW from Seiskari (Лесной), 1000 m.
3. Destroyed or damaged plane: A two-engined seaplane.
4. Where did the plane went down: 3 km SW from Seiskari between two little reefs, burning.
5. Description of the battle: I was patrolling near Seiskari when I spotted two-engined seaplane SW from the island at altitude of 1000 meters. I didn't notice any escort fighters so I attacked. My altitude was 2000 meters. I closed in from behind and below and then climbed to same altitude and opened fire (30 cannon and 120 machine gun shells). My plane slided and the firing hit to the left side of the fuselage and the left engine which started burning. The plane went down to the place I descripted above with two men parachuting. The plane was very large, high-wing, wing attached to the fuselage and narrowing to the wingtip. Single tail, gunner behind the vertical stabilizers and a dorsal gun. The plane seemed to be fast, c. 400 - 450 km/h in vertical flight. I shot it close and got oil and plane parts straight to my plane. However my plane didn't got any damage from them. The wing tips were painted brownish yellow in length of c. 3-4 m.
6. Witnesses: The plane came from grid 119 ol, Ingria.
Own plane
Type and serial: MT-217
W.O Eino Ilmari Juutilainen
1. Date: 23.8.43. 16,35 - 17,20.
2. Area and altitude: Helsinki - Tallinn. 6000 - 10 m.
3. Destroyed or damaged plane: Boston III.
4. Where did the plane went down: Ditched to a shallow water near the beach 15 kilometers NW of Tallinn.
5. Description of the battle: I took off after receiving following message: 18 a 5 aeroplane flying west at high (altitude), 16,30. After take-off I received message (from Raija, the radar): 12 kilometers S from Söderskär. I met the plane soon after receiving the message at altitude of 6000 meters heading west. The enemy plane dived towards surface but I managed to fire at it. The plane ditched c. 15 kilometers NW of Tallinn.
6. Witnesses: The Air Force Depot is trying to raise the wreck to surface.
Own plane
Type and serial: MT-225
Captain Kullervo Lahtela
Both reports are from Finnish National Archives Service (Kansallisarkisto).
Ps. I can help you to find a specific combat report, if needed, from the Finnish Archives. All the c. 3000 - 4000 reports made during the Winter War and Continuation War are there. Just send a PM.