If you have a specialty running store or large athletic shoe store you may want to try on some "racing flats". These are primarily for competitive running, but can make a very good walking shoe also. They are extremely lightweight, flexible shoes with adequate cushioning. They can also be matched to your particular foot strike/motion, i.e. whether you pronate or are neutral. Personally, I like New Balance, Mizuno, and Asics. Not a fan of Nike as they tend to run small and don't have as much room in the "toe box". Also, please know that you should retire your shoes every so often as they break down and lose their support structure. I walk 1200-1400 miles a year for fitness (on pavement), and typically go through at least three pair a year. I am currently trying some Mizuno "Revolvers" with good results. I also like the New Balance 110, which is a racewalking shoe. There are several others and YMMV.
Socks are also an important consideration. At first I tried a lot of the thicker, cushioning socks such as Thorlo, but over the years have found that the thinner the sock the better. Particularly invest in socks that are primarily constructed of synthetic "wicking" fibers such as "coolmax", etc... Also, be sure to cut your toenails correctly - straight across.
Lastly, please take the time to break in your new shoes(and socks) before taking a trip that will involve a good deal of walking. That way you'll be sure that you have a good fit and not have to worry about getting blisters, etc...
The originator of this thread specified not spending more than $75.00. While the shoes I've mentioned above do fall within those parameters, I would not place a limit on spending for the correct shoes if you consider how much you use your feet and how important they are for a lifetime of mobility and quality of life.
My .02.
Regards,