I think I ordered in on ebay, and they only archive a few years of orders, so I couldn't find it. If you search for the replacement power brick, you get something like this. If you find the right picture, it says "8mm 3 prong power" plug. Did some searching and I think it's this. Looks like it's formally called an M8 Sensor Plug (female). I can't guarantee it though, so if anyone takes a chance and learns it's right or wrong - please post here and I'll update the article.