Unfortunately, SNMPv2 is not secure

You betcha its not!

There are GOOD practices for deploying SNMP.
The BEST practice is to avoid V2.
If you must SNMP then use v3
http://searchsecurity.techtarget.com/tip/0,289483,sid14_gci1078248,00.html
http://www.snmp.com/snmpv3/v3white.shtml
or http://www.tcpipguide.com/free/t_SNMPVersion3SNMPv3MessageFormat.htm
if you are feeling geekish.

However my personal view is DON'T DO IT.