[Serra Britt]

Whenever I need a different IP, I use a VNP over a proxy. This one has been working out pretty well for me, although it does reset itself every 6 hours. At least it's the same time every day so once you get used to it you'll know. Most VPNs aren't free but this one still is, and I've been using it for more than 3 months now.

I don't know if this is feasible for what you need but if this doesn't work I'm afraid I don't really know much about any good proxies.