2005 Sport v8: Spare tire dilemma (vs larger 33" mud tires)

So I finally bought what appears to be my dream 4runner (2005 v8), with a sweet yotamafia lift kit (4") and aftermarket rims + larger mud tires that was put on just recently by the previous owner:

• Rims: Method 312s (17" x 8.5")
• Tires:
  $226 FALKEN LT285/70R17 116/113Q C/6 FALKEN WILDPEAK MT01 BW
  Falken WILDPEAK M/T01 LT285/70R17/ 113Q
  • 32.8" x 11"

However, it still just has the OEM spare tire, which raises a few concerns. It'd be nice to have a matching 5th rim + tire but that would mean

• Those cost $$ out of pocket.
• I'd need a tire carrier (and those are $$$$).
• Changing this on the road or trail in an emergency is going to suck - the rim+tire combo is 100lbs!
• It'd take a hell of a freak incident to put a hole into those beefy mud tires. So the chances of it getting a flat is pretty tiny - do I want a full-sized spare just to deal with such a rare event?

I talked to a tech from a tire shop (America's Tire), and he says in a pinch I can just mount the OEM spare, just don't plan on continuing my off-roading trip if I was on one.

• My initial reaction is if I can get away with using the OEM spare in a pinch, that would be great! Even if it means I'd need to cut an adventure short.
• But would that cause any issues (stress/damage to components) if I'm forced to drive long distance on one mismatched OEM spare?
• Any thoughts on this?

Appreciate any insights!

 

I use a 255/75-17 as a spare for my 285/70-17s, in the original spare location under my 06 V8.
The diameter is close, and I have about 1/2" to the pan hard bar.