It was Harris, Harris and Harris Ltd. who designed the RB studio-style range.
A small company set up exclusively for this RB commission, it consisted of Michael, Timothy and Elizabeth.
It does look as if your piece might be RB - but it could be something else. I really can't tell - I don't have any experience of it in this particular colour combination, and it seems to me that similar things have come out of Poland recently - often candleholders or oil burners. I think I'd need to get my sticky mitts on it.