Well, you can use any fly reel.
A cheaper one will require more maintenance.
you'll have have to rinse it in fresh water after use in the salt.
(If I know I'm not fishing again for a couple days I'll strip out the line into a bathtub of water then re spool)
And it's a good idea for some water proof grease on and around the spindle.
A cheaper reel will lose its finish after a time.
But, with maintenance you can extend the life of the reel; it just won't be as pretty.
(I've got a couple cheap ugly ones that are 20+ years old and still function; though they just sit on the bench as spares.
Anodized aluminium holds up to the salt and a sealed bearing help keep the maintenance down.
but the price goes up. (In the 300+ range)
I have 7/8 Nautilus that has seen Pinks, Coho, steelhead as well as chum and a few Spring It's at least six years old
and works like new. Sage has a good one as well and there are others that are very nice but even more expensive.
But whatever reel you get: always rinse it; as the salt will calcify and build up and the line won't slide through the guides as smoothly.