I found recently a website that sell adult baby cloth diapers and onesies. They are a Canadian and I trust them completely. I made a purchase from them a few weeks ago and i am completely satisfied with my purchase. their website is: http://www.babykins.com/ and its completely legit.
I got from them:
-Adult Cloth Diaper with Extra Padding 11500 (neutral (has bears print on them))
-KINS Onezie T-Shirt ORIGINAL 12000 (White)