The Canadian Maple Leaf bullion coins are very respected by investors and collectors alike, likely due to being almost pure gold (also silver, platinum and palladiium). Check out ebay, they usually command about a 10% premium over spot on the retail market. As mentioned, condition may increase value significantly above spot.
Completed auctions:
http://cgi.ebay.com/1979-CANADIAN-M...tem&pt=LH_DefaultDomain_0&hash=item2a0840a6f2
http://cgi.ebay.com/1979-Canada-Map...tem&pt=LH_DefaultDomain_0&hash=item45f3b0805b
http://cgi.ebay.com/1-Oz-Gold-Maple...tem&pt=LH_DefaultDomain_0&hash=item3f0123093e
http://cgi.ebay.com/1979-Canada-50-...tem&pt=LH_DefaultDomain_0&hash=item58887e2685
http://cgi.ebay.com/1979-GOLD-MAPLE...tem&pt=LH_DefaultDomain_0&hash=item3caecb1896
Some info on the 1979 coins.
http://coinhistory.info/maple/
1979
February
* The Cabinet authorizes minting of gold bullion coins for sale on the world market commencing in September. [267.B16]
February 20
* A proclamation amends the Currency and Exchange Act, authorizing the issue of $50 gold bullion coins, with diameter of 30mm, weight of 481.25 grains, and fineness 999.5, effective March 1, 1979. [108.1154]
February 23
* The Supply Minister announces in the House of Commons that Canada will produce bullion gold pieces, called Maple Leaf coins, for a three-year trial period. The coins will contain one ounce of gold, and have a face value of $50. [62.2090] [172.252] [274.29] [331]
(month unknown)
* Supply and Services Minister Pierre De Bane and the President of the Board of Economic Development Ministers, R.K. Andras, announce that a gold bullion coin would be produced by the Royal Canadian Mint. The Gold Maple Leaf would have a face value of $50, and contain one troy ounce of 0.999 fine gold. The gold bullion program is set for three years, with 1 million coins produced in the first year, to be officially launched in September. [19.1]
September 5
* The Royal Canadian Mint launches the gold Maple Leaf bullion coin program. A 1-ounce coin with .999 purity and $50 face value goes on sale in Canada, the U.S. and Europe. [1] [8] [62.2195] [71.2] [152.19] [209.B1] [429.1] [637.1] (September 1 [258.28]) (September 6 [67.684] [169.853] [269.B11]) (September 9? [56])
December 13
* A proclamation changes the weight of the $50 gold bullion coin to 480.71 grains, with fineness 999.9, effective January 1, 1980. [109.5]