The only 1/48 A-6 I'm aware of is from Revell. It was released in the mid to late 1990s as an A-6E TRAM Intruder with the infrared turret under the nose.
I had heard a few years ago that it would be reissued under Revell Germany, but I never saw those claims come to anything.
If you have no hang ups about internet shopping, I think it shouldn't be too much of a problem to find one on e-bay or an on line hobby shop.
Good luck, welcome back to the hobby :-)