DNS IP Request sender - DNS Server stress tester/load tester

I need a small tool which generates 24x7 (always) DNS requests to a list of dns servers which are stored in a config file. The tool should run and produce every hour a specific (see config file) number of DNS requests like a normal client and store the answers in a logfile. Addititional features: * IP Adress from which the request is sent should be configureable (-auto, random from the list of configured IP's for the host on which the tool runs, static from a list, single) * Type of DNS Request should be configureable for a domain (www, mail MX, all, list-all, etc... or even reverse lookup requests of IP's) * Bandwidth of the link should be configureable or at least somehow the bandwidth should be controlable of the link... Budget is small: 100,- USD