No, you can get them really cheap at thrift stores and garage sales.
Well, that depends on "old." Are you talking something like 200 years old, or are you talking about just "old," like 50-60 years?
The quick answer is, not unless they are REALLY old, and usually then, they have to have something that a collector would find interesting, such as material (silver, ivory, etc), decorative factor (carvings, inlays, etc), or perhaps in a set, with a fancy box, such as could have been a gift from a wealthy husband to his new wife, or as part of a dowry. If you suspect what you have could be an actual COLLECTABLE, please do not donate them to a thrift store, or sell at a garage sale until you at least contact a local knitting/crocheting guild. Research them online, if nothing else, they can give you a further contact for what you have. They could be museum-quality pieces, for which you would (likely) not make any money, but you would at least be preserving the history of the craft.
they are worth more in sentiment than monetary value
I have needles and hooks from my grandmas and aunts and they are priceless to me
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