You can search for recently sold items on ebay.
"Click the
Search box. On the
search results page, select the
Sold Listings check box to see
items that have
sold (and how much they
sold for) as far back as the
eBay search engine will permit. Currently, you can go back about three months. Once the
sold listings appear, tell
eBay how you want the results sorted."
Hope that helps, or throw an enquiry in this sectioni:
https://www.ozcardtrader.com.au/forums/non-sport-gaming-cards-general-discussion.72/