Contacted Truglo and they say that SD9VE and M&P 9 sights are not interchangeable. Are SDVE sights different from M&P sights and if so who offers any for the SDVE?

TruGlo is wrong. How do I know? One of my SD9VE's is wearing TG231MPs. She my post (#2) here. The lower one has TG231MPs, the upper has M&P old style steel sights.

Let's see those SD9VE's and SD40VE's.

So any sight that will fit an M&P should also work on a SDVE?

For the most part, yes. M&P Shield sights have the same dovetail, but a narrower slide. M&P CORE sights won't fit.

I put a OEM rear sight for a M & P from Midway and it fit perfectly. The difference is the M & P is metal and the SD is plastic. If you get if from Midway, be sure to also order the little screw.

I ordered a set of Williams Fire Sights for it for about $50. They list them for a SDVE. Since the gun is primarily for the truck and plinking I didn't see the need for tritiums. The Fire Sights work very well in all but complete darkness.
I also have tritiums on my main home defense pistols and they are not without their weaknesses too. Sometimes I question their need at all in most circumstances.

I have a question about this to everyone here. Doesn't anyone now a days use luminescent paint for "night sights"? After all, even Tritium eventually die. The sights on the SD9VE are fine. Like I have said before. It's a 99% and up shooter, consistently.
So why change them? I simply took a drop of luminescent paint to each dot. Bingo night sights that can be renewed over and over again with out spending big $$$ a time or two over the life of a firearm.