I don't know about the actual buttons, but there's an add-on called Theme Font and Size Changer with which you can adjust all the text on the interface: I guess that if you make the text bigger the buttons might enlarge too? Worth a try, anyway, unless anyone else here can give you better advice?

Thanks for the reply. I tried an add-on but it did not have any effect on the control buttons.

I found that I had tried a different add-on. I downloaded "Font and Size Changer" and it does enlarge the buttons on all the toolbars. Thank you for the help.