My "evolve" argument was a way to tell you you have to decide

You can get something relatively decent now and upgrade it later, or wait until you have a..."higher allowance" to get something better from the get go. Up to you and your parents.
You should also push to get that Christmas present early...it's black Friday in a week and cyber Monday just after it; might be a good chance to get it for cheaper than you imagine (and thus get better hardware for the same price)
I however can't really give you an advice for where to find cheap hardware. I'm not from the US, and I could pretty much recommend just Newegg and NCIX, but just because I know them by name and nothing more. Someone from your own country might help you better in this case.