At the bottom of the postal charges section - you will see "Overseas Mail" section.
Depending on the weight of your mail and type of mail - then a price is given.
There is also a link for parcels at the top of the page - to UK - a parcel up to 0.5kg is 874Rs. Each additional 0.5kg or fraction thereof is charged at 86Rs. Maximum weight of parcel is 30kg.
Then customs fees of about 6Rs.
Hope that helps!