Hit google and/or ebay for "vintage mens swimsuit" or "bathing suit." You can also call around to vintage shops in the area - if they don't have it, they'll be happy to call around to their suppliers and find one for you. You'll probably pay handsomely for it - these things are pretty rare. You can also try local costume and theater shops - if you're not looking for authenticity, they might have new ones they've made.
As for the footie pajamas...oh...kay. To each his own:
<a href="http://www.jumpinjammerz.com/">
http://www.jumpinjammerz.com/</a>