He became eligible to play for Scotland when the rules were changed in 1970 to allow players to play for their parents' countries of origin, if they had not already played for their own country.
Wilson continued to play as Arsenal's keeper through the early 1970s, although an injury late on in the 1972 FA Cup semi-final against Stoke City meant he missed Arsenal's 1972 FA Cup Final loss to Leeds United and much of the 1972-73 season.