I think it is so super sweet that your mom saw a blue haired girl and thought "Oh! It's Rei!" I love when parents are accepting of this hobby and even try and get figures for us collectors. My parents would not know where to even start with buying me a figure and even if they did the chances of me opening an authentic figure are slim to none lol! So good on her for finding you a legit one as well!!
My husband on the other hand, has no knowledge of figure buying or sites other than what I tend to gush about to him. Yet, he has access to my forever updating wish list on here, as well as passwords from reputable shops I have accounts for (amiami, HLJ, BBTS, etc). It's never expected for him to buy me a figure so every once in awhile on holidays or birthdays I open a gift and I see a familiar wish listed cutie and I'm so happy and surprised!
Also! At least if you end up reading/watching re:zero you'll have a good start on collecting rem merch!