FHA is the way to go. Your scores are not too low for FHA.
As a direct endorsement underwriter we regularly close loans with scores in the 500's but we are looking for other redeeming factors such as good job stability, more than minimum down, cash reserves, etc......
We are liscenced in PA if you would like me to run your credit. My underwriter, the person who makes the final decision on your loan, will review your credit and pre-approve before you start looking. There is no charge or obligation. Of course, we hope you come back to us when you do find a house.
Email me at email@example.com if you are interested.