I'm very sorry to hear of your sweet Principe Pío's passing, I know how painful it is to lose a bird we have become so much attached with.
I have to say from the pictures, your Pío girl didn't seem so well, that's why on another thread I asked you if she had energy and playfulness. In the pictures she didn't have the big bright alert eyes and she was always too puffy, even for a budgie chick.
Country wise, we are neighbours and here it's also not possible to get handfed budgies by the breeders. I'm a breeder and I don't intervene in handfeeding if the parents are doing a good job, but I do start all my chicks with human socialization and they are sweet, tamed, healthy and balanced birds that have the best of both worlds.
I know you tried your best in caring for your Pío, but in the end the fight was too much for her to bare and she needed more the nutrition of other foods. You have my deepest sympathies. I hope in time you will be able to open your heart to a new budgie, but I would suggest one from a pet store or one from a breeder parent raised and fully weaned.
Rest in peace little Principe Pío. You were much loved and will be missed.