Q:

Inconsistent 503 Service Unavailable using src.sencha.io

The product I am referring to is src.sencha.io. You pass the path of your image into a src.sench.io url, pass some parameters and your image is resized dynamically. I have been receiving 503's inconsistently. 
I have tweeted to Sencha, tried to write on their forums with no avail. I was hoping the community on StackOverflow could shed some light on the service. I am currently using the service in production, so you can imagine the amount of complaints received.
Will this service be maintained in the future and are there any workarounds at the moment? I would prefer not to pull the service entirely. You can imagine my frustration as a developer. I will be sure to never use any Sencha products in the future if this is how they choose to communicate with their developers, free or paid. 
Are there any other similar services around that provide image resizing and retina support on the fly. I do not mind paying for the service.

A:

In addition to my fallback answer which doesn't directly address the question, I haven't used it myself, but keep coming across ReSRC.
Another similar looking one is responsive.io.
This article also has a good write up of many possibilities, under Do I care about relying on third parties?

