Is it possible to use Grafana cloud for OnCall/IRM with Grafana OSS (on-prem)?

We’re running a Grafana instance with InfluxDB backend and are quite happy with this. But want to expand the alerting beyond email. Grafana IRM would be ideal, but a production Grafana OnCall deployment appears quite daunting, especially if you don’t have a Kubernetes environment. Maybe the hobby tag is a misnomer and the Docker version of OnCall is fully functional for small environments?

So using Grafana Cloud for the IRM element paired with the current ‘on-prem’ Grafana seems like a good fit. Has anyone set this up, what are the limitations and is it possible?

Documentation mentions the webhook notifier: Configure the webhook notifier for Alerting | Grafana documentation

But Grafana OSS 11.0 doesn’t come with a webhook notifier as far as I can tell.