Don't skimp on them, but you don't need to get crazy either.

Sights: Cobra Sidewinder
Rest: Trophy Ridge DropZone
Stabilizer: Simms S-Coil
Rope loop
Cat whiskers

Cobra sights are top notch, very bright, exremely durable and reasonably priced.
The DropZone is one of the best rests in the business. It rises straight up and falls straight down. No noise and reliable.
The S-Coil stabilzer is just one of the best. And best of all, it costs less than 20 bucks. But it works just as well as high dollar stabilizers.
You want a rope loop for lots of reasons, but increased accuracy will be the result.
Cat whiskers are great string silencers. I'm not a fan of String Leaches, they are constantly breaking off.