The "cyq" mfg. code indicates that your P-38 was made by Spreewerke between 1943-45.
Are there any other letters or numbers on the pistol?
Generally speaking, the finish on the Spreewerke pistols was the poorest of the lot, and by the end of the war, the machining was very rough with visible circular machining marks.
"OK contition" doesn't tell me very much, but a ballpark estimate of value is $275 to $350.