Lokar makes a "pan fill" one that has a flexible neck and the 90* insert is a hard pipe. Others available from many vendors with the "car-style" where the tube is inserted into the trans.
I just replaced my original pan with a aluminum deep pan. However, because of the pan's larger body my original dipstick (specifically at the 90* bend) interfered with my exhaust pipe. I fixed the problem by taking my original dipstick to a local pipe-supply house and they shortened my original tube and soldered on a new threaded fitting. No leaks here. The threaded dip stick fitting is a common size and available from many suppliers.