Probably trial and error is the best method. The temperature the tiles are fired to and the composition of the clay body are the two most important factors and the seller of the tiles is unlikely to be able to give you this information.
"Fireproof bodies is a popular and indefinite term which simply means those which have a relatively good resistance to thermal shock. It covers two distinct kinds: (a) ordinary ovenware of various kinds ranging from soft-fired porous earthenware to the well known types of ovenproof stoneware, and (b) flameproof cooking ware able,like metals,to stand direct contact with the flame. In this latter class may be placed the soft-fired unglazed cooking pots of West Africa, made from bodies of an extremely coarse and open texture;and in the same class but at the opposite end of the scale, flameproof porcelains fired between 1400 C and 1500 C. Between these two extremes, it seems rather doubtful whether a satisfactory flameproof ware can be made in the stoneware range, 1200 to 1280 C."
Michael Cardew, Pioneer Pottery
In the case of the African pots they are fired in a range of 600 - 670 C.
It is highly unlikely that you can get commercial clay pavers fired at temperatures as low as this.