I think Poole always marks there pieces. I have come by pieces of Aegean with a black backstamp which was extremely difficult to see because it had merged into the colour that was on the base. So it's not entirely possible that the stamp could disappear if it was very faint.
Good point about the white base, we can probably move away from it being part of the Eclipse range. The Aegean range does have this style of base sometimes, usually with an impressed number and the Poole mark.
I just found this company called Tradpots with a range called Sunset...
http://www.tradpots.co.uk/page83.htmlIt doesn't feel like my charger is new though.