Too much. I don't remember seeing numbers for this specific sign though.
An M36R just sold for 3k on an eBay auction and it doesn't have the best pics, but it doesn't seem to be in tip top shape.
Two years ago on Goldin, this NESM37XB sold for 1.5k.
Every now and then when I see a sign for auction, I'll follow it and see what they go for. If I'm not mistaken your sign is rarer than the two I posted. I really wish I could remember the user, but someone had a ton of Nintendo Repair Items, binders, metal signs, just a ton of nice stuff. Hopefully they can see this post and provide some info.