No, I don't think you're being unrealistic but it will not be easy. And it will also depend on if you are looking to go outside of Austin proper, perhaps get a house that needs a little TLC, etc.?
If you don't yet have a Realtor, I would be happy to work with you (at no cost to you), and help you find something that fits your criteria. I have a great team of lenders, inspectors, etc. and work with first-time homebuyers all of the time and have some great resources and tools to help you navigate the process and make it a lot less stressful and complicated than it needs to be.
If you would like some excellent, professional assistance, feel free to call on me!
Joe Jarusinsky, Realtor/Master Instructor, Keller Williams Realty, Austin's #1 Real Estate Company, Ranked #1 by Buyers and Sellers (JD Power & Assoc. 2012)