Mickey meets at the Town Square Theater still, but Minnie has moved to Storybook Circus.
Are you a Disney Visa card member? The characters there are random, but often Minnie and Mickey will be in there together.
Another thought for classic clothes is the Character Spot in Epcot. I don’t remember whether or not Mickey meets there or if he’s with Minnie, but everytime I walk by, I see Donald and Goofy in their classic clothes.
In Chef Mickey’s, they’ll have aprons on over their clothing, so that’s not quite classic - also, Mickey and Minnie come by individually. You might be able to request to get the two together if you’re there during a slow time and they are back-to-back on the rotation.