Need a list of wordpress blogs

Im working on a auto commenting tool for wordpress but I need to test it out on a slightly larger scale than what i have been so far

I need someone with a list of at least 50k+ wordpress blogs
In exchange, I will give you a free copy of the bot

I need the list to be just the blog url, not the post url ie:
www.blog1.com
www.blog2.com
etc...

If you have such a list let me know and we can talk
Obviously to be fair and since I am just testing it, I would only need a small sample for now (like maybe 50 urls) and if the bot is working as expected, we can do the exchange