Punisher built by Paul Delpo here in Connecticut is a great choice(I have his race prepped trans and VB in mine). Woodbine Motorsports sells them and more. AI is a great choice as well. Both valvebodies built by Lightning owners/enthusiasts.
I went to the Woodbine page to order my VB and one of the questions was how often do you tow with it. I do tow my boat 1/2 dozen times a summer. What does this do to the VB if anything and why do they ask the question? I left them this question but never got a response.