If time is more important than gas, harbor freight is your best bet. I'd call them with a part number before you make the trip. I've wasted 50 mile round trips to find that what I wanted was out of stock.
Otherwise, Grigg's McMaster-Carr information is the most useful.
Grigg, if you are going to be at ATHS Springfield, I hope to see you, to say hello.
bucketlst51, What's your first name? I would like to thank you, personally, for your service in Viet Nam.