As Ben says, the Nanamoli translation from BPS is probably the realistic choice. http://www.bps.lk/
Aparrently they are working on a re-typesetting, which will also result in a free PDF. See the post here by Bhikkhu Nyanatusita: http://www.dhammawheel.com/viewtopic.ph ... =20#p32156
As far as I know, the only other option in English is the ancient PTS translation: http://www.palitext.com/palitext/tran.htm
The Path of Purity,
tr. Pe Maung Tin, 3 volumes, 1923, 1929, 1931, reprinted as one
ISBN 008 8 £45.30 « Add to Basket »
One of the most influential Pāli texts, this compendium of Buddhist doctrine and metaphysics is the most important book written by Buddhaghosa. It provides a systematic exposition of Buddhist teaching and is also a detailed manual for meditation. (5th century C.E.)
Translation of Visuddhimagga.