Yes, of course RunBase can do it - you've never see any? You call the class by a menu item button, it shows a dialog on client and then switch to server and execute your business logic there.
Nevertheless AX 2012 has a new framework for this - SysOperation. It will do a lot of things for you, so you don't have to write as much code as with RunBase. Create a data contract class for your three fields, then create a custom UI building class (extending from SysOperationAutomaticUIBuilder, which will generate the dialog for you), implement your lookup method and use registerOverrideMethod() to tell a dialog field to use your method instead. Then associate your UI builder with your contract through SysOperationContractProcessingAttribute,. I'm sure you'll find a plenty of examples, now when you know a few keywords.