I don't think its too late! When one of my budgies died and my little Petrie was all alone, he became super bonded to me. But it broke my heart everyday that when I came home from work all he wanted was snuggles (and food). He seemed so lonely without me (and I worked 8+ hours a day). I adopted another bird from the shelter eventually, and he has been much happier ever since.
Some of the downsides: your bird will definitely become less bonded to you guys. My little P only occasionally accepts snuggles from me now, but loves getting kisses and playing with his brother. Other downsides: be prepared to buy and give two of everything. My boys aren't the best at sharing, so I leave out two food bowls, two treat bowls, two veggie bowls, two avicakes, two of favorite toys, etc. I also have a really big cage. Like a mini aviary that could house 5+ budgies. That helps them get along I'm sure.
Also, if you are sure your little guy is in fact a guy... I recommend adopting an older male bird. I think it is somewhat rare that two male birds won't get along (females can be a little territorial and more prone to bullying and biting your little baby boy). You'll be doing a great deed as well if you rescue an older male from an animal shelter (the older single birds don't always get adopted
). The budgie I adopted was very easy to train too! Budgies are very "monkey-see-monkey-do", so the new budgie just had to watch all the snuggles, finger perching, etc. of my Petrie and in no time he was okay with people (even though he had spent years alone in the shelter).