Most older arrows won't bring what today's will. Many are fairly low spined and have broadheads that are now often considered obsolete. Having said that, pristine arrows of one brand or another may bring a premium from collectors. Certainly that's true for rare broadheads. For an idea of what older stuff might be worth, watch the auction site for a while. Lots of it sells on there every day. Ballpark on what you have, maybe $20 if the broadheads are usable. More if they're rare.