I have some experience with shipping ring and pinions... $13.85 shipping is a bargain!
I like to put my max bid about 45 seconds before the auction goes down. Its a one shot crap shoot but if I bid slow I always exceed what I think the max I should pay. The 45 second technique saves me from myself.
Usually shipping on eBay is ridiculous. From a seller's perspective eBay's shipping calculator is wrong on the low side. I have been burned a few times by it.
BR