You could always consider a free service like Cloudflare which can sit in front of your site and serve the site via SSL to your customers. Yes, it's still unencrypted between CF and your site, however it would resolve the poor "insecure" UX.
As a bonus, CF also has functionality that can re-write http uri's to https.
Hey there, I'm actually the author of the linked post. Yes whilst you're right about doing this the hard way, this wasn't really what I was wanting to do.
In the post I actually outlined that I had actually captured enough data from a handful of remotes that I could have replayed these captures to control the blinds (and I even had a rig set up to do this).
But that's not what I wanted to do. I was interested in working out what was happening with these remotes and being able to generate as many arbitrary remote codes as I wanted.
Going the step further to reverse engineer the protocol is something I did as a learning (and fun and challenging) exercise. I've definitely picked up skills through this process that I can apply in similar projects later down the track.
As a bonus, CF also has functionality that can re-write http uri's to https.