Best place to buy a replacement MacBook Pro battery?

[Overcome]

My 2011 15" i7 Quad-Core MacBook Pro battery is kaput and because this is playing havoc with the date and time settings in turn this is creating other issues the upshot of which is I have to buy a new battery today in Bangkok.

Are there any sensible and viable options other than shelling out the 5700 Baht requested by the authorised Apple outlet I went to last night?

Purchasing online from Amazon, eBay or any other source is for me not an option because I need to have this machine operational today.

I am assuming I have no choice but this approach however if anyone can solve this issue for a lower cost I would be delighted.

[ClutchClark]

I typically go to top floor Terminal 21. There is one tech in the middle of the kiosks who performs repairs to phones. I trust him for all my electronic repairs and service. If he does not have the battery then he can get one from someone nearby. I am sorry I cannot recall his name at the moment.

I cannot vouch for the other kiosks.