In my part of North Texas you could get the 327 rebuilt with a slightly larger comp cam for about $3,500, and to install runs around 1,700.
I went from a 327 non original engine on my 68 and upgraded to a 427 which was the original engine. Engine plus intake, Carb, new clutch and some brackets cost me around $6,800. Plus 1,700 to install.
You might be able to swing the whole thing for $5,000 or so if you do some of the stuff yourself, or know the right mechanic.
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