Maximum number of triangles

I want to upload an item that combines a helmet and an upper body. (Except for lower body and feet.)
I will set the upload as below.
upper_body + helmet as one upper_body slot.
(facial hair, hair, tiara, mask, helmet, earring, eyewear, hat, skin in hiding list)
If I set it as above and upload it, can I use a total of 6500 triangles?
If not, I wonder how many triangles can be used in total.
Also, how many materials and textures can be used when uploading by setting it as above?