Those cluster runtimes are quite old and won't appear in the UI. You'll have to change the runtime with the cluster API https://docs.databricks.com/api/workspace/clusters/edit
If you've never done this before, this is some (bad) code that will help
%python
import requests
# You'll need an access token from the developer settings. NEVER STORE IT IN A NOTEBOOK.
AUTH_HEADER = {"Authorization" : "Bearer " + "dapi0000000000000000000000"}
#will be slightly different if you're in azure
URL = "https:// <your workspace URL> .cloud.databricks.com/api/2.1/clusters/edit"
REQUEST = {"cluster_id": " <Cluster ID found in URL of cluster page> ", "num_workers": 2, "spark_version": "13.2.x-scala2.12","node_type_id": "i3.2xlarge"}
response = requests.post(URL, params=REQUEST, headers=AUTH_HEADER)
# should return a 200
response