Why must it be on a windows platform. If you want a reasonably priced solution just use snort. I don't know of any good IDS's that will run on windows, even if you use Snort, I am sure you can probably still make use of SQL for your Snort logs (I know it can be done with mySQL), for your switch logs, I would recommend going with a standard syslog.

Also if you are looking for an IDS sensor, why not just get the IDS blade for your 6509?