302 Head Question...

All 66-up LA intakes are "compatible" inasmuch as they all bolt up the same. The difference as you know is the size of the port and runner, 318 heads being smaller.

There are 4 pretty common intakes for 318 sized ports; the regular Edelbrock Performer or Weiand 8007, both currently in production, and Edelbrock LD4B and Holley Street Dominator, both out of production. The LD4B is a good intake and still popular, a nice used one is worth $100 when you can find one. The factory iron dual plane 4 Bbl intakes were all large port. There was also an iron small port single plane 4 Bbl intake on the 273, and Edelbrock SP2P's are out there used. The last two are worth their weight in scrap and should be avoided.

You could certainly use a large port intake on the 318 heads, but you won't gain anything, the port is the limiting factor. Sure, the port window can be opened up to 340/360 size, but the gains are probably not worth the cost of a set of head gaskets. That said, there are 2 templates in every 340/360 gasket set.

If your 302 heads have the stock sized valves, just bolt on a Performer, it'll be fine.