According to the ATF database, there are 4 registered FFLs in Chamberlain, South Dakota.
1250 E KING AVECHAMBERLAIN, SD, 57325
206 W CLEMMER AVECHAMBERLAIN, SD, 57325
34458 245TH STCHAMBERLAIN, SD, 57325
34508 254TH STREETCHAMBERLAIN, SD, 57325