100Ah is slightly more expensive than the commonly used 280 (272) Ah cells.
280 is around $85/cell (= 0.30/Ah)
105 is around $38/cell (= 0.36/Ah)
so, its approx 20% more expensive. However, most people prefer 280Ah, since generally this offers the best $/AH, especially if you include shipping.
8 cells of 105Ah will provide 12V / 210Ah, and if you include shipping, 4x280Ah is even cheaper and more capacity, so most opt for that one
Have a look at the current preferred sellers here like Basen or Luyuan, they probably can provide 105Ah, althoug stock is an issue, and with CNY approaching I'd recommend not placing orders before somewhere in March (when CNY is over and companies have been started up).
If you now order them, its going to be a pretty big gamble. Good chances it's not even left CN before CNY, so expect 2-3months before you have them or longer.