Richard,
The 300 Series switches are fully instrumented with SNMP/RMON functions. Pretty much everything you can configure using the Web UI or CLI can be done through SNMP. All the SNMP MIBs for these switches can be found here:
https://supportforums.cisco.com/docs/DOC-13544
The switches support standards-based SNMP versions 1, 2c, and 3 with support for traps, and SNMP version 3 user-based security model (USM).
Also, it supports an embedded RMON software agent which supports 4 RMON groups (history, statistics, alarms, and events) for enhanced traffic management, monitoring, and analysis.
You can use any 3rd party standards-based Network Management platform. You can use Silver Creek, Nagios, SNMPc, MG-soft, Solarwinds or a host of any other Standards-based Management platforms.
Ivor