Whoever bought the windows of heaven(cologne)coin has done well. It recently sold for well over $1000.
http://www.ebay.com.au/itm/Cook-Islands-WINDOWS-OF-HEAVEN-10-silver-coin-2010-COLOGNE-/171211974396?pt=US_World_Coins&hash=item27dd0766fc&_uhb=1
nothing wrong with mixing up two of your hobbies especially when there is such great potential for profit. ive made a small fortune on tiffany art coins.
just before the release of the clownfish the lionfish was selling for about $150 on ebay so everybody thought the clownfish would do the same. i bought 5 and still have 2 left. no big deal but some people went all in and bought 50-100.