good cheap pentax dslr body for first time dslr person

I have my old film pentax SLR lens and want to reuse them on DSLR

Been happy with pentax optio W10 and W30 point and shoot for outdoor use mostly

Would like to do DSLR mostly outdoor and use my SLR lenses, hopefully get nice shots to blow up to 8 by 10 etc etc

Confused on best bang for the buck would like to be somewhere in the 500 dollar or cheaper range

any input appreciated, just too many options out there for a DSLR newby

dave