On the front of my truck is the old Mazda emblem.
http://people.mw.mediaone.net/patfranklin/b4k/clean/front.jpg
Where could I get a new Mazda emblem the same size to replace it?

Mine looks a little bigger than yours. It measures 5" wide by 4" high if you want to check your dimensions. I'm not sure what holds it on unless it's double faced tape. On the back, to the left side is a pin through the grill that looks like it indexes it. Nothing else that I could feel sticking through the grill to attach it. I don't know when they changed to the winged oval like on the 01's, but a dealer is probably the only place unless you can find one, a junkyard might have a newer one around. I'm assuming you want one that looks like the one on the top left of this page.

http://www.mazdausa.com/

I noticed that in 2001 they made the emblem huge on the front, I should check the 98-00 models.

Did you paint the front grill on you B4000 RI? My B2300 is black, but the grill is a graphite-like color. I kind of want to paint it to match the truck, since it matches nothing else.

I didn't paint mine, it came black. I wouldn't want to change it from black anyway because the front bumper is black.