I can not seem to find the Xb10 modem at my local store

Hello! I have recently been having alot disconnects from my wifi and high ping and latency issues, with up and down bandwidth issues. I went online after constant restarts and also have a tech coming out Wednesday, but while I online I found to there is a xb10 that came out in Jan. My store does not carry it. I am a X class member (1.2gb) connection. 

I spoke with people at com/xfin on the phone and they said they don't have anything above xb8. The signals are mixed, how does one get ahold of the upgraded modem?

I am sure my modem is getting replaced regardless, so I figured killing 2 birds with one stone. 

Thank you!