IMHO, and given you are using a Adj. GB...
Your buffer choices would be limited with a AR15 length carbine buffer tube like the PWS Enhanced Buffer Tube... since the .308 BCG is longer, and extends into the buffer tube further.
If your ZEV Tech. ( webpage doesn't want to pull up for me. ) set uses normal length .308 BCG's ( longer then an AR15 BCG ) .... the PWS enhanced buffer tube would limit you to 2.75" buffers. ( Short .308 buffers )
The Armalite pattern buffer system, with its slightly longer buffer tube, allows using conventional AR15 carbine length 3.25" buffers.
IMHO, I would go ahead and try the PWS .308 4.4oz short buffer....that one is middle of the road weight wise.
https://www.primaryweapons.com/product-url-5196
It is hard to say what weight you will ultimately be happy with given your RLGS on such a short .308 16" barrel.... who knows what size the gas port is.
And if the gas port is small enough... you might not even "need" and Adj. GB.
Are you going to shoot suppressed ?
I might even hold off on buying an Adj. GB until I had tried out the barrel first.