I believe my 1984 automatic transmission cooler has failed since I have fluid coming out my fill tube and from all the research I have done on this subject.  I am looking for advice on how to fix the problem.  I figure I have three choices:

1.        Buy a new replacement for $300.  The problem with this is that I only spent $300 for the Vanagon so to buy a part as much as I paid for it is hard for me.

2.       Find a used good one.  Is that possible?

3.       Install an aftermarket cooler kit?  Costs about half that of an original cooler but do they work as well?  I guess if antifreeze doesn't mix with the transmission fluid then it is better.

Any help would be appreciated.  I've only had this van on the road for about a month  and I miss driving it already.
Thanks,
Kevin