Urology is unlike most other fields. It's selective in terms of Step I scores for two reasons 1). more interested than spots and 2) most programs (even those considered "less competitive" or "community") are really solid for whatever future in urology that you want, meaning they are really great programs.
I don't know of specific cut-offs per se but i would imagine that most (if not all) programs screen with the same general criteria. For example if you have a 230 your application will be read and evaluated. If not, you may be excluded even for "lesser" programs. Of course other things matter like LOR, medical school and personal interaction ( like if you've done an way).
As far as I know, there is no generally accepted step I cut off that is abided by all (duh??). Sorry, kind of a paranoid and unrealistic question. Good luck!