Hey Phil,
it's always a gamble buying second hand but I think I don't have anything to loose buying this gearbox for 250$. If the housing and the inside gremlins are good I am golden....if the inside is crap but the housing is good I am silver plated, I'll use my gearbox internals.....and in the worst case scenario I am getting a bad gearbox with a crack too small for the naked eye to see (much better than my crack). That will allow me to empty it, have it welded up while I still drive my leaking glued together gearbox and at the end of the season I can swap things over and most probably have a bag full of spare parts Does this make sense or am I going bonkers?
P.s I most certainly will dye check the gearbox.