Usually proxy list scripts are expensive more than $100 because they can earn lots of money and bring huge traffic. Only several developers are selling public sales. Proxy listing script was good niche industry to the coders.

xrvel is a generous great coder guy. He developed the script for free. The feature is almost same as worth $100 script. You may even delete the Powered By footer from the script.

http://www.proxycoder.com/