Aren't all the LA small blocks the same deck? If so then you can use any intake that is designed for the mopar LA small block motors. As far as the headers go, You may need to have them built with a header kit.

 

78 the earlier a engines are different as from 1956 to 1966 and from 1967 till now so no- the parts are really rare for the old A style .... the headers, camshafts, intake manifolds and cylinder heads like the W-2s are not for the old style A engines so im hoping maybe just maybe some one in ebay or another source like that might have something for him (sorry) but if i was you i might even change over to a 1967 to newer engine if you want to find parts more redely available but i know we all like to keep our cars like from factory spec's ..... hope some one might see this and help you out but id try ebay