Speed, whose 85 caps make him Wales' most decorated outfield player, is convinced both his and Southall's landmark figures will one day be trumped by Arsenal ace Ramsey and Spurs star Bale.
Wales coach Speed said: "My record will be smashed by those two - smashed out of sight in all probability. And they could even get past Neville's because he's only got seven more than I have."
Ramsey and Bale were both on target in Friday's impressive 2-0 win over Switzerland as Wales rubberstamped their revival since Speed replaced John Toshack as manager.
Ex-Sheffield United boss Speed added: "The great thing is they are both totally committed to playing for Wales at every opportunity."