ssc14

I'm a UK student, and in October I'll be starting my BA in History and Economics at Oxford. For those that are not familiar with the programme, I'll be able to take the same economics options as PPE and E&M students, but combining them with a few history courses rather than politics, philosophy or management. Although it's early, I have recently begun to consider an economics PhD, however I realise that my BA is not particularly quantitative. I'm hoping to apply to top 10-20 schools in the US, since funding is not so generous in the UK and the placement records of even the best programmes here aren't amazing. Would a good performance on a UK Master's programme at Oxbridge/LSE/UCL be sufficient to make up for my lack of maths background? What else could I do to demonstrate my quantitative skills? Thank you for your time :)