Bingo. The S2R has an oil cooler but the S4R oil coolers look much cleaner IMO. I especially like the look of the oil cooler on the Testastretta S4R's but still haven't found a used one for sale. An older S4R cooler popped up on ebay thus the question. Thanks for the replies.
I have an extra oil cooler from an S4R...cleaned up, no leaks.