"affordable" is very subjective. Having said that, I use Amazon S3 with CloudFront. Do not attempt to use your own server unless you can cache the contents and anticipate low traffic. Otherwise, your users will see constant buffering.
FREE Windows desktop software for creating and managing MRSS, JSON, and FireTV feeds @ https://github.com/rrirower. No Programming knowledge required.
I have a great deal with several hosting providers. But by far the best deal I have is with volumedrive.com I rent three servers running windows server 2012 r2 (physical machines not virtual) for under 150$ a month. I pay a bit extra for an enourmous amount of bandwidth, each server is on it's own 10gigbyte fibre connection, and have unlimited usage.. I have also noticed that when I enabled multi-plexing in the IIS config it works well for live broadcasts..
I also have other servers around the globe and use windows load balancing with some of my own custom scripts to handle the traffic. But for a smaller setup of like a couple hundred simultaneous viewers the servers would be enough.. If you really want to get into managing your own servers and being in complete control of your destination volumedrive.com is definitely the way to go.. It's also great for renting development servers, they setup in about two to three days and always are an email away for tech support.. Been using them guys for over 5 years and have had only one time with any real downtime. They physically moved thier entire facility and one of thier moving trucks got stolen, was down for 2 days this was about 4 years ago. Then they got me back up and running on brand new servers and even restored my old servers backups from image files I expressed delivered to them (got in my damned car and drove it 4 hours to thier place, fastest way to get it restored, lol)..
I use DaCast for my live streams (https://www.dacast.com/). They have a $19/mo. plan that is a great way to get started until you know how much bandwidth you need. They have a 30 day free trial, and are very responsive and helpful 24/7. They do also have a stream that can be used for Roku Live as well.
I'm using https://ucdn.com they are really good. price starts from $0.008/GB that is really affordable for me. Also they offer one month free to test and if you are heavy user price will go down. They customer service is good too.