I'm a clipless guy, so I haven't really looked. But a couple of thoughts occur to me.
(1) Try eBay. They have a shoe section in the Cycling category. Once you are in it, you can search just for your size or range of sizes so you don't have to wade through 1,000 shoes that you have no chance of fitting into. I have seen old Bata Bikers for sale on eBay before, for example, so you might score something exactly like you described.
(2) Check the Shimano website. Last time I looked (2 or 3 months ago), they had one or two styles that may fit the bill for you, i.e., not wider than necessary but also not with super-aggressive MTB soles but still walkable. They will be SPD compatable, which means that the soles are thicker than you'd normally want, but the soles are are fairly devoid of massive welts and toe cleats that would only get in the way of using clips and straps. I don't think you can order them directly from Shimano, but maybe you can. Also, you can find out the model number from the website and ask your LBS to order some for you in your size.
Good luck. And if you find some shoes that you like, follow the advice of Grant Peterson (Mr. Rivendell) - buy a lifetime supply of them if you can, because when the first ones wear out you'll never find 'em again.