Bulkheads for curved glass

I've seen these before but I don't know where to find them....I'm looking for a 1/2" bulkhead that would fit a curved glass. I'm setting up a 5g vase pico that will be plumbed into my main system, I'm drilling the glass on the side. Anyone know where I might be able to find these type of bulkheads or something else that might solve the problem?

 

Bulk Reef Supply sell Uniseals which are for curves applications like Buckets and such, I am sure that they would do what you want.

 

Thanks, I'll have to check them out. Know anywhere I can get black PVC 2.5" - 3" that's safe for reef tanks? If it's square it's even better...I'm thinking of using it to build an internal overflow on the 5g glass container.

edit--
I ordered the uniseals last night. I'm trying to design this tank as clean as possible, no ugly wires/pipes so these seals should work and look better than bulkheads.