Are there any hints in the Gospels that God would call out a people for His name from the Gentiles?
No. The four Gospels contain no single hint that God would turn to the Gentiles and call out a people for His name. Jesus was meticulously careful not to betray that hidden purpose, though He knew the end from the beginning. God reveals His plans according to His own time frame.
Les teaches that all prophecy was directed to Israel, and no prophecy indicates the Church as such. Not a word in the Old Testament describes this Church Age of Gentile believers. The Old Testament prophets saw the two advents as one, like mountain ranges appearing as a single range from a distance, and did not discern the interval. Even in the four Gospels there is no hint God would turn to the Gentiles and call out a people for His name. Jesus was careful not to betray what was kept hidden in God's mind, though He knew the end from the beginning. Les explains that God reveals things according to His time frame. In Matthew 25 Jesus speaks from the pre-church situation and does not betray the secret; Matthew 24:31 describes the Son of Man coming in glory with angels to sit on His throne.