Here's something we may need a source on:
MULETAPE, a flat kevlar tape used for pulling cable. 1/4" comes in 2 thicknesses good for 1250 and 1500 pounds, and would make really good bear line. The 3/8" versions (two) will handle 1800 and 2000 pounds. I've been using used 3/8 for hammock lines. Fifty feet of the 3/8" weighs 2.5 oz.
Unfortunately, the product is sold only through distributers with a usual minimum of 3,000 feet. I salvaged mine from a cable installation.
Here's the manufacturer's site: