All the types I have available are guaranteed to have an ideal fit between the trumpet and the throttle on the inside. They also feature decent thickness flanges and bodies, a tapered design for max air speed and a full parabolic shaped bellmouth for maximum flow.
Photos:

Pictured are silvertop trumpets that are 43mm long, these are $165 for the set

Showing the internal fitment with the ideal transition between.
here are the lengths available:
silvertop: 43 or 70 or 110mm
blacktop: 50 or 70 or 110 or 150mm
Prices for the silvertop 43mm are $165
and $175 for the 50mm to suit the blacktop for the set of 4.
can make for other models as I have access to these in a 32mm to 73mm inside diameter.
Or even for turbo intakes such as 3,4 and 5" internal diameter