WANTED: Cable modem

Hi I am searching to buy a cable modem. Below are the models.

Motorola - SB 6120
Motorola - SB 5101U
Motorola - SB 6180
Motorola - SB 5100
Motorola - SB 5101
Motorola - SB 5120
Motorola - SB 5101N
Scientific Atlanta - DPC 2100
Scientific Atlanta - DPC 2505
Scientific Atlanta - DPX 2100
Scientific Atlanta - DPX 2100 V2
Technicolor/Thomson - DCM-425
Technicolor/Thomson - DCM-475