No, let's be pedantic. Up until recently, Jr Gent kits were sold with tubes that were compatible with Baron tubes, requiring 13/32 ad 25/64 drills. Barons still are sold with those tubes. So if your Jr gent is more than three or four months old, it will take Baron Tubes and vice versa.
Jr gents recently went metric. I can't tell you off the top of my head what the drill size are now, but they are slightly fatter. Therefore if your Jr gent is less than three or four months old, the baron tubes may still fit if the supplier sold you old stock, but if it was new stock, no, they won't fit.