I didn't try this, but maybe Gitlab's partner offer for Google Cloud, which lifts the credit to 500$ might still be working (link to Gitlab's article here [1], direct link here [2]).

If you or anyone else finds out if this is still valid, let us know :)

[1] https://about.gitlab.com/2018/04/05/gke-gitlab-integration/ [2] https://cloud.google.com/partners/partnercredit/?PCN=a0n6000...