At the moment I'm using Cloudfront as it has support for adding an origin that can be cached, is there any way to setup something similar on DO as would really like to be able to move away from AWS.
You can enable the built in CDN for Spaces and then every object that you put into Spaces will be cached by the CDN but the origin for caching would only be Spaces and related objects there.
We do not have a separate CDN service like cloudfront.
Documentation on Spaces built-in CDN can be found here: https://www.digitalocean.com/docs/spaces/overview/#cdn