You are asking for a lot if you want only informed opinions!  Here is my
guess/opinion: The leak you describe must be from an upper head nut, not
one inside the rocker cover.  If so, then there is no way coolant can
get into the oil unless the rocker cover gaskets leak and some gets in
that way.  Cracks of any kind are still not good, and a long trip could
certainly result in additional cracking or other kinds of calamity,
especially if this is a high mileage engine.

You have to decide if you want to spend your vacation money on vacation
or an engine if you can't afford both
.
Personally, I'd go on vacation!  I could always rent a truck and car
dolly and tow my Westy home if it died.

Stuart MacMillan
Manager, Case Program
800-909-8244 ext 208

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