Depends on how you define comparable..
in the end, the Tundra is still a 1/2 ton truck, compared to a 3/4 ton truck
Tundra is IFS front, Leaf rear... PW is coil/solid axle all the way around
PW has front and rear lockers and disconnecting sway bar
PW has more storage (access to rear seats)
To address those 4 deltas alone could be more than $20K to remedy... and then you're dealing with a highly modified Tundra... and that impacts reliability and warranty.
Comparable, in my mind, means front and rear lockers, winch and moderate (1-1.5") suspension lift using some basic OME or Bilstein components (which is comparable to what the stock PW comes with). IFS is a fundamental design difference with the Tundra; I don't see a point in trying to change that.
Front and rear lockers ~$2.2k
Air compressor ~$300-$500 (depending on the model)
OME suspension lift ~$1800
Warn VR 10k lb winch ~$800
Winch mount ~$500
~$5.8k in parts (give or take a few hundred $). Someone else can do the math on the additional labor costs (though some of that stuff would be fairly easy DIY). We can sit here and pretend that you need to throw the whole catalog and the most expensive parts at a 4x4 pickup in order to make it capable. But the bottom line is you can make a Tundra into a decent offroader for much less than the $15k-$20k that was being thrown around.
But if the OP wants the PW, he should get the PW.