A level maths v IB maths comparison


I’m interested in doing Economics at Cambridge
And currently doing IB1. A lot of the colleges mention Further Maths A levels is preferred/ recommended etc yet in the official website Cambridge has stated HL maths IB is required. Can someone tell me how the to courses equate. Further Maths IB is not offered at my school but I’m lead to believe that HL IB maths is equivalent to further A level.