I talked to Offy a fiew months ago and the manifolds can be ordered directly from them but a better price is available from Summit.
Summit can order them, they are not listed in their catalog.
The manifolds are sold separately as base and top components.
A gasket comes with the base and one with the top.
The weber top is not available anymore.
He said most guys use smaller carbs with vaccum secondaries on the street.
Fuel distribution is a problem on these type manifolds.
The Offy appears to be the same manifold as the GM one, but with a new top that says Offenhauser on it and a couple of bolts are moved on the top to allow removal of the top without having to remove the carbs first.
There are top attachment bolts postitioned under the float bowls on the GM top.
The Offy base seems identical in every way to the GM manifold, other than the missing snowflake for the winters foundry, the top bolt pattern, the GM part numbers.
It does have the fuel distribution dams cast inside identical to the GM casting.
I have an extra single four top for the Offy manifold, if anyone needs one.
Check my web page for First Gen Camaro suspension info:
David's Motorsports page
First Gen Suspension Page
67 RS 327
69 Camaro Vintage Racer
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