I LOVE 327,s and yes its a small jrnl. steel crank, large started in '68. If its original then its tired so I would tear it down and take it to a GOOD machine shop to see what shape the block, crank and rods are in. If you want to build a very limited street engine and want some high rpm then I would buy a good set of forged pistons and give them to the machinest so he can fit them to your block when he bores and hones it. Make sure the crank gets 10-10, mag'd, shot peened and the snout drilled for the balancer bolt.
The stock 327 rods are good when worked properly but for what you want to do I think I'd pop for some 4340 H-beam rods from Scat. I would use ARP main studs or have splayed 4 bolt caps installed. I would shoot for 11.5:1 comp. w/ Edelbrock 60899 64 cc alum heads (under a $1000), an XE268H-10 or the XE274H Comp Cam (still kind of streetable in a 331"). I would use an Edelbrock Air Gap or a Victor JR. intake w/ a 650 Holley D.P. and a good HEI ignition, along with a good set of 1 5/8 long tube headers. An SFI harmonic balancer and flywheel is a must for high rpm use, and have the entire reciprocating assembly balanced. Now there a bunch of ways to build a high winder, a roller cam would be good...but $$$$$$$ I,m sure other guys have there own build but this one will scoot if built and tuned properly.