Looking for Converse CONS ERX 150, where to look?

Hey everyone,

I'm new to the retro/vintage sneaker community.  I am trying to acquire some CONS ERX 150's and was wondering where is the best place to pick these up.  Been scouring ebay and the classifieds but to no avail for the past month.  Are there any websites or other places I should keep and eye out on that may eventually have these.  Understand that these are nearly 30 year old sneakers that aren't manufactured anymore but figured I'd ask a community that has extensive experience in this sort of thing.  Picture is below for reference, really want the white/blue color way.  Anyway, thanks for the help in advance. 

Wish I had anything to tell you other than cross your fingers for a reasonable retro, check ebay or go to docs house with marty bro, sorry.
I think you have a better chance of fishing nessie out of the loch with your shoe laces than ever finding a pair of these that didnt get slept in ,in a dumpster, early in the 90s.