Haven't seen those exact ones, but many like them. Expect a three-digit price for each cluster of four, and you can get those or similar ones from expensive lam

Haven't seen those exact ones, but many like them. Expect a three-digit price for each cluster of four, and you can get those or similar ones from expensive lamp shops that sell primarily to architects. Those shops have pleasantly clueful consultants. If you can't find one, ask for a recommendation from an architect or perhaps an office furniture shop that sells aeron chairs and/or sit/stand desks with motors.