For a valid reason I want to make Tawaaf-e-Ziyaarat and Sa-ee before the 8th.

Answer

Tawaaf-e-Ziyaarat is a Rukn (Fundamental) of Hajj. It is Fardh to perform it. Without this Tawaaf, Hajj is not valid. The time for this Tawaaf commences from Subh Saadiq on 10th Zil Hajj, and it is Waajib to perform it during the Days of Nahr (i.e. 10th, 11th and 12th Zil Hajj). The permissible time ends at sunset on the 12th. If it is done after the expiry of these three days, then although it will be valid, the penalty of a dum (a goat/sheep) will apply.

The Tawaaf which you intend performing before these days will not be Tawaaf Ziyaarat. Your Hajj will not be valid.

Sa-ee may be made on the 8th after donning Ihraam and making a Nafl Tawaaf in which Raml and Idhtiba are also made. If Sa-ee is made on the 8th, then it is not necessary to make Sa-ee after Tawaaf-e-Ziyaarat.