It seems the Quest For The Mask booster packs are pretty scarce on Bricklink, though they can be found on eBay pretty frequently. Unfortunately most of the sellers are far too optimistic about the demand for these.

This listing of 13 booster packs for $39.99 USD with free shipping is actually very reasonable though, and comes up to about $3.08 per pack. You can also make an offer on them, although I’d have have already bought them for the asking price if I had disposable income right now.

There’s also this auction for a Toa Inika store display that doesn’t take up an entire shelf! The seller thankfully had the courtesy to warn buyers of some issues;

From Toys R Us

Arm had to be glued back because it fell off

Sometimes lights up with new batteries but not guaranteed to work I couldn’t really get it to

matthevelazque4

The current bid is already at $150.00 USD, and you can sometimes find more impressive store displays for that much. Not many have the button to activate a play feature like this one though, assuming you can get it to work reliably.

UPDATE:

Discord user Kohi spotted this interesting BIONICLE 3 pack up for auction on ShopGoodWill.com. It appears to be a Chinese 3 pack including a Vahki, Visorak, and Toa Iruini sealed in exclusive packaging. I’ve seen or used this site before, though it looks like it might be worth checking through every now and then.