Rear Duster Tire Size

It's less than not ideal. A 1/2" from the outer lip of the wheel to the inner edge of the quarter? You need at least that much to keep from rubbing if your tires are going to be inside the wheel wells. So if you're not counting on your ride height to keep the tire and quarter from ever occupying the same space the best you could do would be something with around a 7" tread width (same width as the wheel outside edge to outside edge). Even that may not work, depending on your ride height, because the section width will be more than 7". Even a 215/70/14 with a 6.6" tread width has an 8.7" section width, which would mean the widest part of the tire would hang out more than 3/4" past the outer lip of the rim, or a 1/4" into your bodywork if they're the at the same height.

So your next question "is it ok to run a wider tire that may stick out?" is what it comes down to. Is it? Only if your suspension is stiff enough, or the ride height is high enough that the body of the car and the tire can't ever be in the same place at the same time. So, either you need to have at good 3" (or more) from the tire to the quarter, or you run suspension stiff enough that it limits the upward travel of the wheel to less than the space you have between the body and the wheel. Lots of people run tires that won't fit inside the body of their car. Usually with SS springs, so 160 lb/in springs that also raise the ride height so there's at least a couple, if not a few inches between the body and the tire. Of course ride quality and handling are out the window at that point, but it's all about what you want.

If you want your tires to fit inside your wheel wells, even 215/70/14's might be a stretch depending on your suspension. It looks like you have some rake, but you also have some relatively short tires (sub 25"). Taller tires will also reduce your body clearance. If you don't mind the '70's "stink bug" look with the rear end of the car up in the air and the tires hanging out like a bro-dozer then you can run whatever you like. But if the suspension ever gives enough to allow the tire to hit the body you'll be in trouble.

If it were me, I'd be looking for some 15x7's with at least 4.25" or more backspacing. But that's just my opinion.