Good question. I'm assuming you mean night sight, and not the actual red dot sight, in my reply. They have a S&W OEM night sight at Brownells for about $60. It is listed as fitting the 40V but not listed as fitting the 40VE. I haven't called to ask about the fit for the 40VE because I want it cheaper and Brownells is backordered (out-of-stock). Of course AmeriGlo doesn't make one for the Sigma but I'm about to see if the same principle of this HIVIZ thread applies as I've just ordered a Glock AmeriGlo front sight "fits all Glocks". It probably won't be in for a week or two but I'll document the process with pictures here.

I bought it for $34.99 at GlockWorld plus S+H $4.95. I also bought some other stuff because GlockWorld has a flat ship rate for any sales amount except ammo. They had it for $32.97 at cheaperthandirt but S+H was over $10. As cheaperthandirt is in Fort Worth, I would have to pay Texas sales tax, which is not insignificant. I don't pay sales tax at GlockWorld. The AmeriGlo part number is GL-112. It looks the same as the night sight pictured in post #105. The height is listed at 0.165". Width is 0.140".

I got interested after handling a S&W SD40 which comes with a tritium front night sight. (Actually, I think the night sight is really most of the dollar difference between the Sigma and the SD.)

Lets face it, if you need the gun for self defense in darkness, you only need to see the front sight. In fact Dr. Ignatius Piazza has a multi-million self-defense training facility in Las Vegas and his company is called FrontSight.

I know we are working on budgets here so I'm going to do it as inexpensively as possible without sacrificing quality.

Not trying to be a tease. Just wanted to give out the info in case someone else wanted to try this at the same time. I DON'T YET KNOW IF THIS WILL WORK.

Two general questions I have:

1) Is the sight attachment hole on the 9VE the same size and shape as on the 40VE?

2) I've seen Locktite Red and Blue both used on this thread, Red is stronger than Blue and may destroy the part if removal is attempted. Which is really better for this application?

One other note, I was confused about the Trijicon and AmeriGlo references for the same sight. Turns out that AmeriGlo makes the metal sight housings, ships them to Trijicon who makes and installs the tritium tubes in the housings and ships them back to AmeriGlo who then sells them as AmeriGlo night sights.

Scientific note: Tritium is radioactive with a half-life of 12 years, meaning that your AmeriGlo sight will lose 50% of its brightness every 12 years. It emits low energy beta particles which have a range of about an inch and won't even penetrate the stratum corneum of the skin. The particles likely don't even get through the metal housing. So it won't set off radiation detectors at the airport. It's perfectly safe unless you break the tube and swallow it.