I actually prefer vintage design (e.g. Nokia 8210, designed by Kenzo), but unfortunately these old phones aren't compatible enough, 2G networks are phased out and are already switched off in many places.
im not sure you can have flip + modern in a phone. ive never seen it anyway
if the idea of having a flip phone is so that you will be less distracted then maybe a flip case might help to do something similar. preferably one that has really loud velcro so that people around you will get pissed if you keeping opening it every 2nd minute to look at facecheck