Thanks for the info. That's interesting. The spec sheet marcins linked to in the opening post is in fact not of a newer, but an of older version of the PLF 503759 from shown in the picture. Here's
the datasheet for the .06 version, with the 66663 type number shown at the start of the serial number in the picuture.
So the DR1000 indeed came with a 1300mAh battery and the 1140mAh mentioned in that thread is wrong (probably from an older type spec sheet as well?). Unfortunately, that means picking up a 1200mAh battery from Amazon or eBay
, doesn't get one back to full orginal capacity. As I'm not too keen on those white label batteries anway, I'll keep hunting for a Varta for a bit longer.