you know, considering the small back seat, I'd want a seat that sits really low, too, as head room in a 2-door for carseats and boosters can be tricky.
I'd probably get the Evenflo Sureride - it has 19" top slots, goes to 65lbs and it's inexpensive... sure, it's a convertible, but because it will sit so low and doesn't convert to booster, it won't take up as much space up and down. As long as he won't be taking it in and out of the car, once you install it (and I'd do so with latch if you can get it in tight that way, just to make it less likely that it could uninstall by an accident of someone hitting the button on the buckle), all you have to do is get the basics drilled in... harness tight, above shoulders, chest clip at armpit level
the other options I'd look at are the Evenflo Maestro and SecureKid 300/400
Also to others, please remember that 2yrs old ff is perfectly acceptable. Not everyone can do ideal. We have worked so hard to finally get 2yrs to be the minimum and we have to remember why we wanted it as the minimum... because it is the true reasonable minimum. Yes, we now finally have seats that easily rearface MOST kids past 2, but we have to be realistic and understand that most of america is still working at getting on board with the 2yr minimum. A child is 100% safer in a properly installed properly used seat than one that isn't so, but is facing the rear.