Hi
Yes you should be able to try / register an evaluation of SRM.
Login to my.vmware.com and navigate to this link http://www.vmware.com/go/try-srm and select 'Register Here' on the right-hand side.
Or you can also go to My Evaluations to check if your SRM evaluation license has expired, then you can select 'Start an Evaluation' and choose 'VMware vCenter Site Recovery Manager', and select 'Register Here'
If your existing account has expired SRM evaluation license, you can try registering a new my.vmware.com account.