I stumbled upon this horn the other day, only place I have been able to find them is on ebay.
http://www.amazon.co.uk/PRV-Audio-WG45-50-Waveguide-4-Bolt/dp/B00K2ETCLM
Anybody have any experience with them. Remind me of the P audio 4525 and Goldwood 450 expect without the diffraction slot. Wonder how they sound? I guess based off of the specs, they couldn't sound any worse than the other two. Maybe for the price I will give them a try.
One bad review was that bolt holes were drilled wrong, but I figured I have a drill and can take of that. I should see them by next week and will let you guys know.