David,
The 300lb barrel swivels and #10 split rings will get you started, no problems.
Again, like the connection question, you will get various opinions on whether barrel or ball bearing swivels will do...... I like Yozuri and Sampo 300lb 2 ring- ball bearing swivels while NT barrel swivels are excellent too (ask Crusty about these, or search the forum about NT's).
Unless you are trying to dong a monster, #10 split rings will do.......I keep #10H and #11's for some of the Brisbane spots since the GT's can be very large!
Cheers
Aaron.