The Oxycheq 40# single tank Mach 5 wing is a good one if money is no object.
VDH has a 35 # wing that’s similar to the Oxycheq in style but they are out of stock right now AFAIK.
There’s also the DGX Gears 30# single wing which is a direct knock off of the Oxycheq in style and measurements.
Those are the primary super streamlined narrow “trick” wings.
There are a few other narrow wings like Mares and Apex but I’m not sure about max lift on those and if they have anything 40# or thereabouts.
Beyond that you start getting into wider wings which still work fine but are shorter and wider like OMS, Hog, Hollis, Halcyon, older Oxycheq if you can find one used, and a whole bunch of others.
A lot of it depends on your plate too, and whether you plan to use a STA or thread the cam bands through the plate. This is where it gets tricky because generally any wing can be used with any plate if you have a STA because all of them should have 11” center holes. But not all cam band slots in wings line up with cam band slots in the plate, and if they do there is still the issue of some sort of roll control device to stabilize the tank on top of the channel of the plate which not all wings have.
Some wings do not have cam band slots at all.
So maybe a better place to start would be to find out what kind of plate you have and if you plan to use a STA or not?