For the tx02 you can do the whipp mod and change that heavy cloverleaf antenna for a diapole one. The weight difference is not that much, but everything counts. You have some great youtube tutorials about that. Also you have alternatives in banggood. CM275t is only 3,5gr ( i think it is the same that PJC recommended)
As PJC said, you can save some more weight changing the frame. You have also the e010s frame. It’s 3,5gr. If you buy it in banggood be aware that it will be delivered bent because they don’t ship this cheap products in a rigid packaging. You can fix it throwing the frame into boiling water 1 or 2 minutes. It will recover its original shape.
You can save maybe 1 more gr if you cut off the ducts of the frame. Theres another alternative, it is using the frame stiffener as a frame, and you use only motor mounts from the frame. Everything is attached with double sided tape. Works great
JST PH 2.0 is the way to go. That debate is beyond discussion.
Sorry i can mostly recommend banggood stuff. Is what i have tested. Beecore fc works great