Does anyone know where I can purchase a nice, but reasonable, 60th wedding anniversary cake topper?

define "reasonable".... of course the most reasonably priced is the one you make yourself. You might try your hand at making figures of the happy couple...I saw one recently that was not only the husband and wife but all their children, grandchildren and great grandchildren ...each sitting on the tiers going down the cake.

Isn't the 60th wedding anniversary the "diamond" one? If so, you could do something with crystals to give a sparkly effect.