Why not get a real 2600 then? That experience will certainly be much better with the real thing, because you will have physical objects that look like real game cartridges. I think that is the most sustainable option.
You can get a Harmony Cartridge that takes an SD-card so that you don‘t have to buy every single game available just to find out it actually sucks.
If it is mostly about the physical form and you really must buy a new console based on an emulator, how about the 2600+ ? At least that can play 7800 titles also, and it can read real cartridges.
