Try www.zanottimotor.com Go to the shop online liknk, then the price quote link and put in the part number. To get price with shipping put it in your basket...
I've had good luck with Surdyke as well. I know some have had issues but their shipping seems to be more in line if you are just ordering one part. It may also take a bit longer to receive from Surdyke.
I got mine from Zenotti's, good service, good price, fast shipping, a tough combination to beat.
Just check their stock when you order, if its out of stock it may take a couple of extra days to get it.