Apple themselves offer a battery replacement service for a fee, and it seems to be a reasonable fixed price (where I live). You might still be able to get them to upgrade that Macbook's battery.
Don't use an Apple Reseller for this without checking Apple's battery replacement price first. The reseller I went to quoted 2.5x the price, and said they were unaware of Apple's price (seems unlikely), which they could not match.
Don't use an Apple Reseller for this without checking Apple's battery replacement price first. The reseller I went to quoted 2.5x the price, and said they were unaware of Apple's price (seems unlikely), which they could not match.