I did all the shops except for the 3 shops that are listed as "not available". I found 10 blocks.
Then I read the information on the sampler page. This is what it said:
"The blocks circulate through the "Prize Verification Confirmation Page." This page appears after you have successfully registered for prizes on the "Prize Verification Page." When you find a block, click on the block to download a PDF of that block and assembly instructions. Also, check your list of visited shops in your member area to re-download block pdfs you have missed downloading.
Remember that the blocks are moving around all the time, so you may need to check the shops more than once to find them all—a great reason to revisit your favorite shops!"
So I went to my list of favorite shops and found the bunnies again in those shops and found the final two blocks.
I had long stretches of shops/bunnies where I didn't find a block so don't be discouraged.