273 Intake Manifold Question!

Hi all, I've been running into issues locating an aftermarket 4-barrel dual plane intake manifold for my 1969 Dart 273. Even Summit Racing is stumped by this request. I see no advertised 4-barrel intake manifold for this engine, only for the 318/340/360 ci small block engines. I understand there was a cylinder head change after 1966 for the 273, however there is no reference that I have found that indicates I can use the other small block manifold for my '69 LA273. They seem to all advertise for the larger displacements with no mention of the later 273 ci displacement. Please advise. Glenn
273 and 318 have the same size ports in the head. Edelbrock Performer and Weiand Action Plus intakes have the 273/318 sized ports and will work fine on your 273.