Fader Pot Identification

Have a slide pot that I need to find a source for. The number has a square with an M inside and followed by 50k.
Then either an 8 or a B.
Then 113AVN.
This is for an NSI model NCM708 Microplex light controller. I can get them from the manufactuer for $10 each, but need 16 of them and would like to find a cheaper source.
Tried to google with no success.

I would hazard a guess here and say that you need 50K B(Linear) sliders with 113mm of travel end to end, but I'm guessing and could be wrong.

So, you're saying that the "B" means linear taper, I didn't know that, thanks.
The slot for the travel is 2 inches, so not sure what the 113 means.
I'll keep looking.
If someone can help me identify the logo, the square with a M inside, that would be great.thanks

The "M" mark is for Meggitt, the travel on their standard parts is either 15mm, 20mm, 30mm, 45mm or 60mm.
According to my data, the 113 is the resistance, ie 11K, although there is clearly a mark on your part for resistance. I suspect that it's a slider made specifically for your product and not one off the shelf, hence the marking and odd travel length.

Here's a datasheet for their standard parts:

Thanks a lot for the info, I've emailed Meggitt for a possible source here.