osclass postcode + radius search

I need a mod for my osclass site running latest version. I need a postcode + radius search function. Users will be able to type a UK postcode (eg N1 8DD) and select distance (eg within 5 miles, within 10 miles..) and then will be shown relevant ads. I also need the distance from a searched postcode to appear on the listings (eg 2.2 miles away)....(must work properly and show corrent results within correct distance) please only apply if you have worked with osclass before.