speedorob86, check this out:
http://www.jockstrapcentral.com/swimmer-jockstraps.php
The ones we wore back in the day were pretty much like this one:
http://www.jockstrapcentral.com/prod...?product=16101
Keep in mind the Speedos (or whatever brand) were less brief than they are today - typically had 3,4 even as much as 6 inch sides. Those almost were what we call today a square cut. Typically we wore them for modesty as compared to protection like you might need in other sports.