It is a 360 intake port and w2'ish exhaust port. It is NOT a bigger port version 302.
The 308 head has better exhaust ports raised up floors then a 302 head. It also does not have a closed chamber like a 302 head it is its own head in fact people say it is a j intake port with a smaller W-2 styled exhaust port.
They are $386.99 after core charge
So after tax...a pair will run around $850.00.
Who wants to spend $850 on a stock head with all stock Parts with the exception of new exhaust valves, no hardened seats, no performance Springs Etc.
However... if you need a single head....it's a lifesaver. I have one good 308 head and I also have a pair I have already ported to 273 cfm @2.02/1.60 that are still 3/8 and #were with a semi tulip 2.02 340 valve...so they might flow a touch better with a nail head valve.