You remind me of when I kept on putting off getting a Leviathan. I ended up paying a lot of money buying the parts separately in order to build one. That's OK because I love that rocket and had fun building it.
I emailed Estes customer service telling them how we all love the C11-3 and especially the C11-5 engines. Let them know that you would like them to reintroduce those most beloved engines. You can find their email address at
www.estesrockets.com/contact-us
Members, please take this opportunity to email Estes and tell them that you would like to see the C11-5 brought back. You can also leave a post here for Estes to see how you feel.