Hi David, I think you'll find all the info in the Scrapbook article I mentioned. "Barney's Beanery" made multiple Columbo appearances, on way or another, in both the early and the later episodes. I don't recall that the restaurant in "Uneasy Lies The Crown" is identified, but Columbo is served in that place by John Finnegan, who later became the "regular" proprietor of Barney's Beanery.
Barney's itself -- the "Columbo" version -- underwent a couple of revisions over the years in its internal appearance, but the outside shots were always authentic, and the "Ransom For A Dead Man" scene appears to be, at least in part, actually shot on location.
I've never been there, but, the next time I have an opportunity to be in Los Angeles, you can bet I'll be making the pilgrimage out to West Hollywood for a bowl of 3-alarm chili.