A 1050 4gb vram is not rare at all. Is just a laptop version of the gtx 1050. I was interested to find out that this fact is unpopular. There is a huge misconception that any gtx 1050 with 4gb is a TI model, but the reality is that there are so many models of each of the gtx 10 series that aren't ever really promoted. You only find that out once you attempt to buy a new card.
Recently I was looking at a 1060, and omg, I wasted a whole hour looking into the differences of the following sub-models: GV-N1060G1 GAMING 3GD, GV-N1060G1 GAMING 6GD, GV-N1060G1 GAMING 6GD V2, GV-N1060IXOC-3GD, GV-N1060IXOC-6GD, GV-N1060WF20C-3GD, GV-N1060WF20C-6GD, GV-N1060XTREME-6GD. Yes, these are literally 8 different models, or if you wish 4 different...