Welcome to the Forum!
What reel do you intend to put on your rod? Do you intend to use a detachable fighting butt?
If you are worried about saltwater corrosion, the most bulletproof reelseat is a Fuji graphite, such as the DPSM. Yes, Fujis are ugly as a hockey puck, but are just as tough and corrosion proof. I don't think the Fuji fly/spinning seats have a hood aligning feature. I wouldn't use a detachable fighting butt with a Fuji.
Lemke offers an uplocking titanium reelseat (TITA) that would also be corrosion proof and tough as nails (
Southwest Custom Rods).
If you are conscientious about washing your rods and reels after a day on the water, anodized aluminum should be fine. Pick your favorite style. The REC RSLS seat would fit over the McFarland blank and be a smaller diameter. The RFTS seems to be a big rig reelseat. Personally, I don't think an 0.75" OD reelseat is too large on a 6/7 weight rod.
Tom