@imparanoic, ok thanks for the suggestions. So your idea is that I buy a Nintendo DS (I see from Carousell should in the 100-300$) and then I buy separately the Game&Watch compile, so for example the below, is this correct ?
FYI the ones that I am interested in: Octopus, Popeye, Chef, Turtle Bridge, Snoopy Tennis (very hard !), Parachute, Life Boat, and Chef.
The slight concern I have with the originals is the condition not so much of the casing itself, but the buttons. As I recall after a few thousand of hours, they wear out and are hard to manipulate so cannot play anymore (even worse they can split). In fact I can tell from some of the pictures as the clearance of the button is very small meaning the game won't play well. That's my biggest concern. So perhaps your idea would work better even if it's not exactly what I wanted initially.