KB Olds gasket help

Guys, many of you already know I'm running a KB olds tall deck in a mild blown alky combo. The questions I have pertain to the intake sealing. Unfortunately I have a short deck manifold, so I need to run the spacers. I've heard nightmares about spacers leaking, so I'd like to be sure to seal this thing up good.
The spacers are machined for o-rings on both sides, is it necessary to run an addition gasket on either side of the spacers or not?
We're can I get the o-rings for the...

KB Olds gasket help