I don't know if you found an intake or if this is something you want to try. Years ago one of the mopar magazines used a LA intake on a magnum motor. Maybe because a carbed one didn't exist at that time. To make it work they took a die grinder to the intake holes so that a bolt could be fit vertically into the magnum head. Then they took thick wall tubing and cut one side to match the surface angle of the intake and the other side was cut square. This adapter was used with the bolt to bolt on the LA intake.
The magnum heads don't have an exhaust cross provision so it may take longer for the intake to warm up in cool weather.
I believe as state above if you buy fuel pump eccentric parts from Hughes engines it will allow you to transfer your timing chain cover, fuel pump, water pump and accessories' to the magnum motor