Welcome to Bladeforums Nito3.
First, I would suggest that you contact SOG and see if they can send you replacement screws. Although it's doubtful since SOG is owned by GSM.
If you have to find screws yourself, there are multiple characteristics of screws that you will need to identify to find replacements. T6 and T8 are only torx driver sizes.
Here are the things you need to know-
Diameter of the threaded portion of the screw. For standard sizes (SAE) a few likely possibilities are 2-56 or 1-72, if metric, a few examples would be M3 or M2.5.
Thread pitch (type and number of screw threads)
Screw length (the length of the threaded portion of the screw).
SAE or metric (if the knife was made in Asia the screws are most likely metric).
And if the heads of the screws are countersunk in holes in the handle, you'll need the right head diameter size.
Here's a possible shortcut for you, see if you can find any other screw you have that will thread perfectly into the holes of the knife, maybe one from another knife, then take that screw to a hardware store and see if you can find a match for the diameter and thread pitch. Some stores carry screws as small as 2-56 as well as similar size metric screws. Then if they don't have exactly the length, head, or drive type you want you can order screws online from places like usaknifemaker.com or knifekits.com.
I don't believe that there are any places that specifically sell replacement parts for the SOG Trident.
