When I was looking at getting the 2008 Highlander, 240k at $3400, then I ended up with a 2010 Sienna, 210k at $4k, same drive train, better condition, less mileage, similar cost. Go see
YouTube's Car Care Nut on both these and the others he may have that share the same drive train. What I learned that would discourage me is the external head gasket leaks and the engine must get removed for many repairs. I did take his advice and got the older 3.3 motor in a 2004 Sienna, good build quality and DIY friendly.
I almost broke even selling the 2010 (should have waited that out...) and got the 2004 at $1500 and the DIY better fits my garage style. Student loan debt should be a low interest rate, but you'll feel a lot better if you pass on a big cost here and sunset the debt sooner. On the other hand, drive what you like, but keep it maintained. Ohh, almost forgot, 10k oil change interval might have been the standard, though worse if the 4 cylinder, the 3.5 does have a ~6.3 oil capacity with filter exchange, just be aware of what to look for in terms of possibly being a oil burner or other wear concerns, this should be fine at that mileage.