What do you mean ‘simulate’? You can’t ‘simulate’ SERPs. You can automate the pulling of indexed sites from keyword searches. Is that what you are talking about?

SEO PowerSuite has an app called RankTracker. As far as I am aware it’s the only software/service out there that does true localization SERP. Meaning, you can actually pull rankings based on geography, something that popular services like Moz, Ahrefs, etc can’t do. I highly recommend that software also. There’s no limitation on amount of campaigns or keyword phrases you can track also.