I come from a fairly strong OO background, the benefits of OOD & OOP are second nature to me, but recently I\'ve found myself in a development shop tied to a procedural prog
I don't think you'll find a study like that. At least you should define what you mean by "cost". Because OOP designing is somehow slower, so on the short term development is maybe faster with procedural programming. On very short term maybe spaghetti coding is even more faster.
But when project begins growing things are opposite, because OOP designing is best featured to manage code complexity.
So in a small project maybe procedural design MAY be cheaper, because it's faster and you don't have drawbacks. But in a big project you'll get stick very quickly using only a simple paradigm like procedural programming