Am i good enough for oxford?

Basically i am a gap year student and i have acheived A*-Biology, A-Maths (90 in c3, but 73 in c4) , A-Economics, A-Chemistry in my A-levels.
I am looking to apply to do economics at :
Oxford- (Eco and management)
Warwick-Economics
Bristol-Economics
Durham-Economics
Kings college-(eco and management)

Are these realistic choices??
I have captained my school football team at various levels, won economics prize at my school, read a few books about economics.

Are these university choices realistic?? Any other units that you could suggest which would be better choices?
I really enjoy economics and really want to do it at uni, any help advice would be appreciated

Yeah, those results are amazing!
I don't know the entry requirements for Economics at those unis, but I'd imagine you'd probably get offers seeing as you got straight As. Plus most unis only ask for three A-Levels, and you have four
Doubt you have anything to worry about
Although, I would suggest you get a job or do some voluntary work or something over your gap year because if you get uni interviews, chances are, they'll be asking what you've been doing with your year out!