Exchange 5.5 to 2000 Migration Tool

I am migrating a small network of about 50 -100 user Exchange 5.5 Box to Exchange 2000. I need a few suggestions on Exchange Migration Tools. I have reviewed a couple NetIQ, BindView etc; they look good, but too pricey. I need something not too robust and reasonably priced.
Thanks in advance for suggestions and comments

Boak