There were PR Spitfires, other Spitfires, Hawker Hurricanes and two seater conversions of both. There were A.W. Albermarles (a gift to the people of Russia from King George VI). There was at least one DH Mosquito may have been more. There was (Post War) use of at least 2 or 3 Lancasters.
The first Spitfires to come to Russia were a few PR Mk.IV which arrived at Vaenga in September 1942 after overflying German held territory. While they wore Russian markings they were actually flown by RAF pilots, and around twenty sorties were made above the Kola Peninsula and over various Kriegsmarine bases in the area during operations known under the “Orator” codename.
After that they were handed to the VVS-VMF North Fleet and were assigned to the 118th ORAP.
A second batch of 143 Mk VB, came through the Persian corridor, being transported to Iran aboard the “City of Lille” and “Baron Inchcape” and were used in the Kuban area. They were assigned to the 7th IAP, and 57th GIAP, as well as other units. These aircraft were extensively involved in the air battles over Kuban during the April-May 1943 period. Note that those aircraft were clipped wings rebuilt RAF aircraft armed with both MGs and Cannons. Some of them were later retrofitted with Russian armament like the Hurricanes. Note that the Merlin engine caused some problem to the Russia as it was not as rugged as some Soviet designed and serviceability suffered a bit. Even if the Spitfire was quite successful over Kuban it appeared that the Merlin engine was not giving its best at the altitude the Russian used them. So after this battle, the units were re-equipped with soviet aircraft and the Spits were handed over the PVO units and assigned to defense of Moscow and Leningrad. Indeed the PVO was responsible with intercepting high flying aircraft (mostly recce), a task which suited the Merlin engine better.
The last batch of Spitfires was a batch of 1148 Spitfire Mk.IX, all of which being assigned to the PVO units. These aircraft were delivered in 1944, and saw little combat except those in the Leningrad area, where they reportedly engaged the FAF aircraft.
Units known to have used the Spitfires :
118 ORAP (PR Mk. IV and Mk. V)
7 IAP (Mk. V)
25 ZAP (Mk. V)
36 IAP (Mk. V)
57 GIAP (Mk. V)
821 IAP (Mk. V)
11 GIAP (Mk. IX)
16 IAP (Mk. V & Mk. IX)
26 GIAP (Mk. V & Mk. IX)
67 IAP (Mk. V)
102 GIAP (Mk. IX)
177 IAP (Mk. IX)
767 IAP (Mk. IX)
20 IAP (Mk. IX)
Spitfire PR IV
Soviets had at least three machines of that type and all were used by 118. MRAP (Naval Recon Air Regiment). These planes were armed with... PPSh machine pistol carried behind pilot's seat.
There was some problems with spare parts, but Soviet technicians made everything to keep'em flying - i.e. when original Dunlop tires were out of order, they replaced them with... MiG-3 wheels.
First 35 planes were carried to Basra (Iraq) on Jan 10th, 1943 aboard s/s "City of Derby". Rest of 143 planes were carried till the end of March 1943 - some planes were damaged (I.e. 5 Spits aboard s/s "City of Lille").
All planes were "second hand", but after general repairs and changes in equipment (i.e. R/T TR1133 were replaced by older TR9D).
Other unit using Spits VB was 236 IAD (Fighter Aviation Division) where two planes were used between March and July 1943.
Only about 30 Vb were transferred to PVO units. 15 were used by 16 IAP PVO at Lubercy near Moscow.
Soviet Union got 1185 Spitfire IX fighters - almost all were LF IX version and only two were HF IX.
First 6 Spits of that type arrived to Basra on April 5th, 1944 aboard s/s "City of Eastborn". Initially planes sent to Soviets were after general repairs but later planes were straight from factory.
Most planes (825) were sent to PVO units. In summer 1944 Spits LF IXC/E were assigned to 26 and 27 GIAP near Leningrad, 16 and 177 IAP PVO near Moscow, 767 IAP near Murmansk and several others.
One Spitfire HF IX was assigned to 16 IAP PVO, where Russian called it "Spitfire 9G"
There is no reports about combat use of Spitfire IX in Russian service.
All info from an article published in Polish aviation magazine (unfortunately not existing now) "AERO-Technika Lotnicza" 12/91 and written by R. Bock, D.B. Khazarov and W.R. Kotielnikov.