Yes, both Splunk Enterprise and Opsgenie offer a Free Trial.
Splunk Enterprise is designed for Large Enterprises and Medium Business.
Opsgenie is designed for Large Enterprises, Medium Business and Small Business.
Pricing for Splunk Enterprise Starts at $150/Month whereas for Opsgenie Starts at $9/User/Month when Billed Yearly.
Some top alternatives to Splunk Enterprise includes Reveal, Sprinkle Data, Data Monkey, Knarr, Iteratively, Splunk Cloud, Easy Insight, dataSights, Squirro Service Insights and Data Suisse.
Some top alternatives to Opsgenie includes Freshservice, Jira Service Desk, PagerDuty, VictorOps, Amixr, AlertOps, Splunk On-Call, Spike.sh, Mission Manager, StatusCast Incident Management and PagerTree.