Help Needed for Posting 500 XML's

Hi Smartbear Support,

I want to post a set of 500 XML's one after another. I would like to create 5 XML's which should run for 100 times. Each time, an unique RFC ID in XML should get changed ( ex: xyz, xyz+1,xyz+2 etc.)
Let me know how to make this possible ?

Thanks in advance..
Vijaykumar VK