The 4/0 will work for chunking but if you get into doing this regular you will want (notice not need) an upgrade there.
What kind of price range are you looking at for the spinner setup? This can go from a few hundred to a few thousand. I believe there is a thread in the offshore section or saltwater section titled something like budget reels with good info in it.
The basic setup for tuna regulars is a 4/0 size something for chunking/trolling, a spinner for casting, and a jigging setup.
Highly recommend dont spend a bunch (which is relative to you) on equipment until you have made a couple trips because you will know much better what you want.
Can someone explain how the Feds count recreational Red Snapper catch?
"Pretty sure it involves a witch doctor, an astrologist, and a tub of KY jelly." - jamisjockey