Have you tried the stock jack? I have a 3" lift and I can get any wheel off the ground with the stock jack with room to spare. Rear wheels are easy since you are lifting the axle, but the front is a frame lift behind the front wheel. I should also note I'm on stock sized tires.
I have not done that offroad yet, but I have a hi-lift base plate that'll stabilize and lift the base of the jack a little bit.
There is also safe jacks:
Safe Jack - 4WD, Outdoor,Off road, 4X4 accessories and products.
and I found a guy that makes top adapter for the stock toyota jacks here:
Jack Adapters - Land Cruiser Products - LCP
I've asked on the safe jack website if their adapters will fit over the toyota bottle jack and haven't ever heard back, but based on measurements, it wont work. Which is a bummer, I'd like to get their extension set, but not sure I want a hydraulic bottle jack to use it.