It's listed as "Deluxe" so I don't know if that means just lights, or lights/sounds, or what. Vader was Deluxe IIRC and he was NOT cheap.
That said, I think price is sometimes determined by reusability... The Battledroids are all new tooling but easily repainted to get a few uses, so I'd think R2-D2 falls into that category somewhat, but electronics can bump something a lot I think.
Those myriad of opening panels too... Looks complex.
I'm thinking this could be over $200 easily. Less than $300 though. Just my guess right now... Depends if he just lights up, or lights/sounds, and how complex that lighting is. It looked like it might be fairly complex. It's a much more pricey/complex tooling than the Battledroids too, IMO.
I'm just guessing though, and not an expert. This could be off the charts expensive though, or just on the charts expensive.
If it's metal, which I doubt but those doors seemed to be some kind of metal or magnet, I'd say that would increase any cost by a ton. Didn't they do an all metal 3PO? I don't know what he cost, but he was pretty damn expensive IIRC.