I have had an Epson Expression XL10000 for about 6 or 7 years now and LOVE it. They are not cheap, I paid around $2500 for it then, not sure what you could buy them for now or buy a used one for, but I highly recommend it.
I have to scan original artwork for production by the manufacturers that license my work and it has met their quality standards along with ease of use for me.
It has an oversized bed in the range of 13" x 18" plus or minus.