Hey
If she's been on her own for a while now it will probably very difficult to introduce another hamster. Chances will be quite high that they fall out. I might be wrong here, and please somebody who knows more correct me, but I think hybrids are very likely to fight even if they have never been on their own for a while and they are usually kept as single hamsters. You would have to get another cage with wheel and everything in case you have to separate them.
Where do you usually get your hamsters from? A pet shop or a breeder? I am asking because almost all my hamsters were sexed incorrectly by the pet shop and if that happens to you and you actually put a male hamster to your female you will and up with a lot of hamster babies!
May I ask why you are thinking about getting her a buddy?
All my hybrids were happy on their own. I personally wouldn't do it if I were you