Narrow HIGH back booster?

[greenemami]

Sorry if this is a repeat, but I searched and only found narrow low back boosters-I definitely need the high back!

Anyone have recommendations for a narrow HBB?

We have 3 across with a RF radian (though I need it to fit FF too, since ds is almost 3 and will probably turn FF in the next year or so) and an 11-year-old in a seatblet.  Ideally would fit in the center seat next to the radian.

Any help is appreciated! Thanks!

[chickabiddy]

How tall is the child?  The Harmony Dreamtime is a fairly narrow highbacked booster, but it isn't terribly tall.

[greenemami]

She is about 47-48" tall, almost 6 years old, so I do want it to last several years still I think-when is the recommended age to switch to a low back booster?  She is quite tall, though she is more leggy than tall in the torso. 

Thanks for the rec, I will check that one out!

[greenemami]

Bumping because I need to make a decision and would love any other input :)

[LeighPF]

The Graco Turbobooster is the same range as the Raidan width wise with the cupholders tucked in, as is one of the evenflo ones. I was just researching this topic this week.

[greenemami]

Thanks-I just tried both the turbobooster and evenflo amp.  Neither fit well in the middle seat where I was hoping to put it, but either would work outboard with the radian in the middle.