I did a web search on my DW's model number and the word "leak" and it led me to an Applianceblog.com article (RIP, Jake!) which had a link for the part at AppliancePartsPros. com The cost and next-day shipping fee was very reasonable and the "how to video" was a very welcome (and well-made) surprise! My DW model does not have the drip pan, so I set an old baking pan with a water alarm under the dishwasher to guard against future leaks.
Thanks APP!!