Question on Leaky Transmission

[James Lofgren <lofgren@xxxxxxxxxxx>]

Richard,

I recently purchased a 1989 535i that is great (i.e., immaculate, 47K
miles, periodic synthetic oil changes with Redline), except that it appears
the transmission leaks about a drop each day - it might need resealing?

I plan to have this fixed, but am uncertain to whether I should have a BMW
dealer or a transmission shop do this.  The local dealer is 35 miles away
and there are a couple of local reputable shops (so I have been told).  

Does anyone have opinions which would be better?  I suspect that the dealer
will charge more than the local shop, but is the extra $$$ justified?
Is this truly an esoteric job only to be done in the hands of a BMW master
technician?  And, if a transmission shop does the repair, should I specify
o.e.m. or aftermarket gaskets?

I would appreciate some input, because, as you may suspect, at this point I
know next to nothing at this point out BMW maintenance.

TIA,
Jim Lofgren

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