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Sony is killing off recordable Blu-ray, bidding farewell to disc burning | TechSpot
(www.techspot.com)
This is a most excellent place for technology news and articles.
I'm not sure what country you're in, but have you tried Amazon? I found Verbatim 50 packs of 25GB for $40 and Ridata (usually good quality discs) for $28. If you want small amounts there's various 5 packs for less than $10.