I just looked on amazon (searched: grid brolly box) and they are available apparently (I don't have grids). (LINK).
I probably should sell my Fotodiox. It's bowen's mount. Great shape. I just have to find a way to box & ship it, because I'm sure the shipping would cost more than what it's worth to truly buy it used. It's on Amazon for $100 new basically. It would no doubt cost way too much to ship to be worth it to someone, which is why it just collects dust with me. Unless you know a better way to ship something that doesn't cost $60+ for something that big, since I don't have contracts with UPS, etc, like these companies do.
The only problem is that's a 31" grid and we're talking 46" here. I'm not even sure if I would need one but I'd like the option and was just making sure that the Neweer had velcro on the inside rim to hold a grid and I guess it does.
And yeah shipping costs can cause a problem with buying certain items but I figured I'd just throw the offer out there if you were ever thinking of selling it. I can see by recent posts though how it looks like that Fotodiox can put some stress on the strobe at certain angles which I don't really like. However it does have an available grid which is a plus. Now if the 46" just becomes available on Amazon is a different story. I really don't need either but I'd just like to have a big octo just in case.