For the Apollo missions, there were covers made with ship cancels for the ships that were part of the U.S. Navy Recovery Force. Here are some for the Apollo 11 mission (first man on the moon). I apologize for the less than ideal color balance. A primarily white background with just a small area of color confuses my scanner into imparting a slight yellowish tint that isn't present in the original. I can process it out, but that causes the perfs to become invisible, so I left it as-is.
USS Ozark (MCS-2), Atlantic, stamp is Scott# 1371 (issued May 5, 1969).
USS Ozark (MCS-2), Atlantic, stamps are Scott# 1331 and 1332 se-tenant stamps (issued Sep 29, 1967)
USS New (DD-818), Atlantic, stamp is Scott# 1371, common AM below 24 variety
USS Goldsborough (DDG-20), Pacific, stamp is Scott# 1371, common AM without dots variety
USS Hornet (CVS-12), Pacific, Prime Recovery Ship, stamp is Scott# 1371, the more common machine cancel type II
USS Hornet (CVS-12), Pacific, stamps are Scott# 1331 and 1332, the more common machine cancel type II, but is either missing the AM slug, or it's too light to see (it should be visible in the light blue bottom of the 5 cent denomination numeral)