Suddenlink → [Connectivity] D3 Modem

Is there any way to rent a D3 modem from Suddenlink or do I need to purchase one? I've been renting a modem from them since I signed up. (D2 SB5101) While it was fine for a long, long time, lately I've been seeing reduced speeds in the normal peak time hours. (5pm-12am)

I'm on the 15/1.5 package and during these hours I get anywhere from 5-13mbit. It mostly stays around 6 or 7 mbit though.

I think its more economical to just buy one.

In my market, they sell them too.

Do you know for sure your area is upgraded to take advantage of D3 modems? It might help with your situation if your node has more than 1 downstream channel you can bond to.