Someone please recommend me template for 10inch Hifi Subwoofer Cabinet..(for home use)

I am trying to start a small business and I am starting with subwoofer(PASSIVE), Can anyone please help me with suggesting a good 10 inch ported Subwoofer Cabinet, with slot design..

I actually want to build cabinet with Walnut wood with our local Artisan work (lookup Kashmiri Walnut woodwork), should I make entire cabinet with Walnut, or should I just cover insides with MDF and outside with Walnut..

What thickness walnut should I use, If I only use Walnut and what thickness if both walnut and MDF.

I want to target midrange, like around 250USD. Just building my first unit here, I have sourced connection port, Driver and everything else(gonna be Passive to begin with).

Local Artisans are suffering, I know a local guy, this might boost his business if it works well, thinking of building Bookshelf speakers are well in the future

Any help is appreciated