Sadly, No. I'm in the market for one too and think I have a decent used one located but I don't know for sure yet.
The basic drawn well for the shoe box Fords that is available through several vendors, might be made to fit but a person would have to do a lot of cutting, bending, some fabricating, and welding to make one work in a Merc. That may be what I will do if the used part I'm looking at doesn't materialize. It might be easier to fabricate from scratch too but I haven't seen one of the Ford wells in order to see how far off it is. For aproximately $130 a guy would want it to be pretty close in curvature and a few other dimensions. One of my Mercs has a Flinstones style well in it now and isn't even a good pattern to make decent repairs. Luckily one of my other Mercs has one that's still in pretty decent shape for a pattern if I end up going that route.