My wife and I were talking about these today.   According to Google,

Mills Fleet Farm has 6 roll books
https://www.fleetfarm.com/detail/wrigley-lifesavers-hard-candy-sweet-storybook-6-8-oz-/0000000273742?gclid=EAIaIQobChMIpJqc2NyU2AIVF7jACh1J4wzCEAQYAiABEgJCqfD_BwE

Walmart and Target have 5 roll books
https://www.walmart.com/ip/Life-Savers-5-Flavors-Hard-Christmas-Candy-Sweet-Storybook-6-8-ounce/46089013?wmlspartner=wlpa&selectedSellerId=0&wl13=1020&adid=22222222227000000000&wl0=&wl1=g&wl2=c&wl3=42423897272&wl4=pla-51320962143&wl5=9019866&wl6=&wl7=&wl8=&wl9=pla&wl10=8175035&wl11=local&wl12=46089013&wl13=1020&veh=sem

Amazon
https://www.amazon.com/Lifesavers-Hard-Candy-Sweet-Storybook/dp/B01N8Q3YPN/ref=sr_1_1_a_it?ie=UTF8&qid=1513640298&sr=8-1&keywords=lifesavers+roll+books

I did not see a 12 roll.