Technically you are sitting for variant paper not a stream paper (ie : tax & law). If you take different stream you must you use that stream text book.
In case of variant you won't find much different in content & syllabus but minor difference ($ = RM, Mr Smith = Encik Ali......)
Malaysia will be fully compliant with IFRS after 2012 & international variant will the best to follow (however if you pick other variant doesn't matter)

BPP only publish acca books in UK version / stream / variant since its a UK company. You won't find anyone printing malaysian acca textbook yet.
Don't worry just buy the book (it will be quite useful to familiarise yourself with the question style) However some question can be too realistic / too much application.
Kaplan book is another good alternative but BPP is more professional while kaplan is more student based.
You can buy those books through some acca tuition provider in KL (if you wish)

If i am not mistaken you can buy them at centre provider at KL (if transport & location is not a problem)
Mcorange : sells BPP (its located near masjid jamek station : beside TM headquarters)
FTMS : possible BPP (opposite central market : between KFC & MCD)
KSA : possible kaplan (near Pasar Seni, at plaza nationwide 11th floor)

If you are looking for books on tax / law you can buy on your own (most examiners publish their own books : but mostly for tax like Chong Kwai Fatt & Richard Thornton (he is P6 examiner).