You may purchase a tag3 board from one of our partners e.g. Avnet (China)
You should use a TAG3 evaluation board for your software development purposes because it has LEDs, headers, and buttons, plus the ability to recover (reprogram) if the EEPROM gets corrupted during your efforts. The TAG3 board uses the stand-alone (discrete) System On a Chip (aka SOC) 20737 device.
If you insist on using a board that uses the 20737 "module" (aka SIP) package, you might want to consider using the WICED-Sense evaluation board. It's less expensive, but not an ideal development platform because it was not designed for that purpose.
I don't know if anybody is using the SB-BLE-S02 PEVB, as that is very antiquated. Plus this board is populated with the 32K EEPROM device. Everybody has jumped up to the 64K EEPROM (which is what's on the 20737S module). Note: There is a SB-BLE-S03 PEVB that does have the 64kbyte EEPROM, but again... both of these evaluation boards (SB-BLE) are not ideal development boards because they are very-very limited with headers, buttons, LEDs, etc. Use the TAG3 eval boars! :-)