How about this?
def distswith(fn='fit'):
"""prints out distributions with '.fit' methods.
where any class with a '._pdf' method is considered a distribution
"""
import scipy.stats
for fn in dir(scipy.stats):
fns=eval('dir(scipy.stats.'+fn+')')
if '_pdf' in fns and 'fit' in fns:
print fn
EDIT: looks to me like all 86 do.