Gastonia rhymes with:
estonia, antonia, estonia, latonia, tonia, adonia, amazonia, ansonia, antonia, caledonia, colonia, cydonia, diaphonia, donia, estonia, gonia, harmonia, idonia, latonia, macedonia, madonia, new-caledonia, omonia, patagonia, petronia, philharmonia, rondonia, sidonia, sinfonia, slavonia, slovonia, sophronia, tonia, vernonia, vidonia
Gastonia sounds like:
gaddum, gaetano, gaitan, gastineau, gaston, gathman, gatien, gatten, gatton, gaudin, gaudino, gautney, gayden, gaytan, gayton, gedeon, gedney, geodyne, gestation, getman, gettin', gettman, gideon, gidney, gitana, gitano, goddam, goddamn, godden, godin, godina, godine, godino, godman, godown, godwin, goeden, gooden, goodenow, goodin, goodine, goodman, goodnow, goodwin, goodwine, goodwyn, gosdin, gotham, gotten, gottman, gudino, guidone, gustin, guston, gutman, gutmann, guttman, guttmann, gutwein, guyton, gyohten