Over in the UK, while there are unfortunately no super-compelling offers for the Seagate Xbox Storage Expansion Card, the WD Black C50 (1TB) can currently be had for £118.68 (was £149.99). Not a world ...
If you want to play those games again, you would need to transfer them back to your Xbox's SSD. Seagate's and Western Digital's Expansion Cards are plug-and-play extensions of your Xbox's SSD.