G'day there mate, proud Aussie and am more than happy to complete this task for you in no time. Courtesy of friends at the various universities, I have access to the recording booths at Queensland College of Arts (Griffith), University of Queensland and Queensland University of Technology. So not only can I provide you with these 20 short phrases but those short phrases will be studio quality as well.
I also have a dear friend of mine, who is my assistant conveniently enough, who is happy to also volunteer her voice as well, so not only will you get 20 male short phrases but 20 female short phrases as well. (Unless you just want the one set of 20 recorded phrases, in which case all good, but I figure I offer that nice added bonus)
I look forward to working with you shortly. If you accept me for the task, I will arrange for a booking at one of the studios and have the recordings sent over in due course.