The Jerry Parker reproductions were very popular for many years and I think a reasonable proportion of all the commemorative stamps up to about 1970 were done this way. These are most likely .99 silver though I have seen some of his done in copper as well.
Have not seen any for years but the last time I noticed any on
ebay they actually went for between $*.00 and $15.00 - I think it was about 5 or 6 years ago. Try a search on
ebay because I imagine they pop up quite regularly in some category.