Charlie,
Here are a few team issued items from around 1970.
In 1970, the Orioles switched from B&W postcards to color versions. From 1970-1972, the same photos were used. The best way to identify the 1970 postcards are the smaller font used for the printed name.
1970 Postcard
1970 Postcards 11 - Copy.JPG
The Orioles also printed three different borderless style postcards of Bob Grich, Davey Johnson and Brooks Robinson. They are often listed as 1969, because of the sleeveless photo used for the Davey Johnson postcard. However, I believe these were done sometime between 1970-1972.
Borderless Postcards
1969 Postcards (Borderless) 01 - Copy.jpg
8x10 photos are also tough to date, but I believe these are around 1970, possibly 1971.
Team Issued 8x10 Photos
Robinson, Brooks 16 - Copy.jpg Robinson, Brooks 13 - Copy.jpg
1970 Publicity Photo
1970 Team 2 - Copy.JPG
One last card is from the Orioles Pictures of Champions set.
1970 Pictures of Champions #1 - Copy.jpg