Yes, you can buy two 10" subwoofers and build a box to suit. However, there are pros and cons to doing just that. If you want to keep the factory tool kit, you will only be able to use one. ( assuming you want to retain the rear seat and not lose utility of the backseat )
Choosing a subwoofer, there are many to chose from... some require large boxes and have weak motors. Some have tiny box requirements, but very strong and large motors which will be too deep to utilize.
There are vendors that have boxes already built, it's probably more economical to go this route, unless you like math and carpentry. Choose a suitable subwoofer based on the internal volume of the box in cubic feet and the mounting depth.
Amplifiers: most are too deep to be mounted on the rear cab wall and have the seat fold up and down. If that's a concern, then you might want to choose another mounting location. I used under seat mounting, but you have to do a bit of fabrication and modification to fit amps under the front seats.