Random Banner

I have been using a bit of php to place a random banner. It reads a file and uses very specific format

http://page-to-link-to, http://image-file.jpg

Amazon has some new banners I want to put in rotation but the format is different

<iframe src="http://rcm.amazon.com/e/cm?t=my-affiliate-id&o=1&p=48&l=ur1&category=electronicsrot&f=ifr" width="728" height="90" scrolling="no" border="0" marginwidth="0" style="border:none;" frameborder="0"></iframe>

I was trying to find a module or droplet that might let me insert a block of random text or individual text files - so maybe I could drop in the html for each

<iframe src="http://rcm.amazon.com/e/cm?t=my-affiliate-id&o=1&p=48&l=ur1&category=electronicsrot&f=ifr" width="728" height="90" scrolling="no" border="0" marginwidth="0" style="border:none;" frameborder="0"></iframe>

and

<a href="my-link"><img src="my-image" /></a>

any thoughts appreciated.

I don't change the banners often enough since I manually edit the file currently -tedious- and the new amazon banners are randomized by amazon which will keep my banners fresher.