Crosswordiee.com

% replaces any number of letters (la% - lake, lamp)_ replaces one letter (ca_ - car, cat)

Crossword clues for Mex., U.S., etc.:

AMER: Mex., U.S., etc.
OAS: Group comprising U.S., Mex., etc.
AMER: Can., U.S., Mex., etc.