It shouldn't be! Every mount and pet that came in a DLC bundle has always been available for purchase by themselves.
I will kick everyone's butt, even my own.
Star-Sïnger - Khajiit Magicka Sorc - EP Legate - Flawless Conqueror
Falls-With-Stars - Argonian Magicka Templar - AD - Former Empress - Voice of Reason
vMA/vBRP/vDSA no death/vHel Ra HM/vAA HM/vSO HM/vMoL/vHoF HM/vAS +2/vCR+1/vSS/vSS Yol HM+Lokk HM