I’ve bought 4 extra batteries for my Canon EOS 300D. Eur 6,99 for 1 battery through Rundumdieuhreinkaufen ;-) a webshop. Delivery within 4 days (including weekend). Battery does not have 1250 mAh as written on the website but 1500 mAh
So thumbs up for Rundumdieuhreinkaufen!
Canon Branded BP-511 batteries are priced from Eur 17.50 to Eur 45 a piece!