The Juniper Virtual SRX firewall can run on multiple platforms, but VMware Workstation is not mentioned in the list of supported platforms. Having some experience with both, I know that almost all VM's designed for the VMware ESXi environment will run on the (stand-alone) VMware Workstation product.
I downloaded the .ova file from the Juniper website and imported it in VMware Workstation v12.1. During the import I adjusted the number of CPU's to save resources, which turned out to be a mistake. The VM really needs the two CPU's, because if you don't it just won't work (routing failures, etc..). So, don't change the defaults for CPU and memory.