It's kind of difficult to suggest a monitor based on the posts that I read previously, but I would recommend Korean monitors if you're wanting to overclock.
I recently purchased a Qnix monitor and was able to overclock up 144Hz without any issues. Gaming on that monitor is seriously awesome!
I purchased my monitor from www.overclockmonitor.com
where they seem to have a variety of monitors, but make sure you have Paypal. I tried paying directly with my credit card, but they asked me to create a Paypal account for security reasons. Also, the monitor was shipped from South Korea via DHL and I got it in 3 days.
Anyways, hope this helps and maybe you'll able to find the monitor you want from them.