The 486 is Mitchell's big high-speed saltwater spinning reel, the faster sibling of the 386. Both were introduced in the late 1960s and appear in Garcia's 1973 catalogue as upper-range saltwater reels with stainless steel internal parts and room for about 420 yards of 15-pound line.
It was built in Cluses, France, for surf, pier and inshore fishing, and it is much scarcer on the used market than the freshwater 300 family. Our latest snapshot found only nine listings, at $80 to $135 delivered for working reels, with asks jumping to $265 to $330 for boxed reels or listings claiming rarity.
In that snapshot the same seller had two near-identical 486s listed at $89 and $265, so compare carefully. The bigger saltwater Mitchells seize if they were put away wet, so look for photos of a clean bail roller and a spool that turns.