I moved the post to another forum.
As I read your original post I apologize I thought you were asking about a Gov thing so no you cannot get an E5 now.
Unfortunately, E3 is the highest there is now. (even for subscriptions other than Partner)
I'll be honest
@tomlop the best way to get a great way to build apps, test and get some free azure credits is to sign up for a Visual Studio Professional subscription.
now.. its not free.. its an investment, but you will have access to a full Office E3 Tenant with 25 office licenses, Power Platform development with full Premium access, power automate, devops, Github, and a bunch of free software, licenses for cloud stuff including D365.
Its a yearly, tax deductible purchase. Year only is roughly 1,200 and after that 850.
I know its a lot to look at and I have never written this up for anyone as a suggestion, but just go check it out. You get so much out of it (5 licenses for D365), you get dataverse, your own tenant, you can have multiple development environments.
Its getting hard to get a whole package of things. The only other real way is to be a Partner and purchase a Silver level (for you) package.
or go here if you haven't
Cheers.