There’s an obvious recommendation here, namely the pink Yamaha P-32 Pianica that you see on Amazon. The P-32 is an excellent first melodica. I have a large collection of current and vintage melodicas, and the P-32D has consistently been the one I play the most. You’ll see reviews if you look at the blue model on Amazon, including a review by me. The pink model is identical except for color.
This one has free shipping from Japan, which usually takes about two weeks if it is in stock. I have had no problems with shipping from Japan, either in terms of reliability or in terms of quality of packaging.