Vol.4: Mahavagga. 529p.-Vol.5: Cullavagga.440p.
OBNB doesn't sell books, but you may be able to find a copy at one of these websites:
The Book of Discipline (Vinaya-Pitaka) by Vinayapitaka. Published by Luzac in 1952. Publication and catalogue information, links to buy online and reader comments.
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