With what you are building, a custom is almost a requirement. Most likely a 10" with a blower motor, needs to be a strong piece. There are a couple 10.5 " Hughes that look like they may be blower pieces from the wants at the bottom(blower pulley), and a 10" Chance bolt together on RJ for sale, but used would be a crap shoot unless you know the owner that had it. There is a local guy here that can build one as good as any, uses all new parts, billet steel stators and covers. I have one of his 8" converters in mine and ran quicker than my Coan. If you don't like it he will buy it back. Can't ask for any better. Make it spragless as well. Ask for Greg
http://www.fticonverters.com/