The Casecom is about £30 with delivery ( competitor )
The 300 is £45 from OcUK with free dly.
I would 'find' the extra £15 for the 300.
If you have to save for another month to get the extra, then its worth waiting.
Set your hardware up on a mobo box for a temp solution.
a lot easier than installing it in a 'cheap' case that you'll be replacing in a while.
If you buy the casecom, then you'll struggle to sell it later - So a waste of £30 imo.