I posted above, but starting log-store.com so I'm trying to promote it in threads without being too pushy :-)

It's in beta and free. My plan is honestly to have my pricing be free for small amounts of data, and then 50% the price of Splunk for larger data sets. Just show me an invoice, and you'll pay half!

(co-founder here) Try axiom.co - we support splunk-like query syntax, dashboards, monitors, unlimited sources/hosts/etc, and you get 500GB/mo ingest + 30 days retention on the free plan.

OpsVerse allows you to bring up Grafana Loki for logs.

There's also Logz.io or you can use Elastic for an ES backend.