[RMc]

Let's take these one at a time (*IBAF members):

Cambodia*: 95% ethnic Khmer, a few Vietnamese and other Asians.

East Timor: Austronesian (Malayo-Polynesian), Papuan, small Chinese minority.

Guam*: Native Chamorros (57%), Filipino (25.5%), White (10%), Chinese, Japanese and Korean ancestry.

Iceland: Icelandic (Nordic/Celtic origin). A small minority of Eastern Europeans in recent years.

Israel*: Jewish (75%), Israeli Arab (20%), "Unaffilated" (mostly from the old USSR; 5%).

Mauritius: Indian/South Asian 68%, Creole 27%, Chinese 3%, French 2%.

Mongolia*: Mongol 90%, Kazakh 4%, other 6%.

Nauru: Native Nauruan (a mix of Melanesian, Micronesian and Polynesian; 58%), other Pacific Islander (26%), Europeans (8%) and Chinese (8%).

Sao Tome & Principe: Well, it's complicated. Some mix of African and Portuguese (with a sprinkling of Chinese) should work.

Solomon Islands: Melanesian (94.5%), Polynesian (3%) and Micronesian (1.2%).

Sri Lanka*: Native Sinhalese (73.8%), Sri Lanka Tamils (some native, some Indian; 18%); Muslims (8%), a few European descendants

Surinam: A diverse mix of East Indians (37%), Creole (31%), Javanese (Southeast Asians; 15%), "Maroons" (descendants of African slaves; 8%), White (5%), Amerindian (2%), Chinese (2%). Whew.

So it looks like you're gonna need about another dozen ethnicities to run the table here. I'd start with the five countries (*) that are actually members of the IBAF...