Can I include this as an extracurricular activity?

I was heavily involved in numismatics (coin collecting) for around two years, spending lots and lots of time researching and buying coins to add to my collection. My collection grew reasonably big, but due to the expensive nature of collecting coins I’ve stopped pursuing this as an “extracurricular” for about a year now.
If I was still active with it, it would no doubt count as an extracurricular.
My question is if it would be ok/honest for me to list it as an extracurricular now, even if I’ve since stopped. My interest is still there, anyways, maybe in the future when it’s more affordable for me I can continue.

Sure, go ahead and list it, but don’t misrepresent your current involvement.

List it. It’s unusual, interesting, and probably helped you develop business-related skills.