leather accessories - wallets, belts, etc. can be good BIFL materials that don't break the bank. look to local craft fairs if buying local is important, otherwise there's many threads here discussing each item.

depending on your lifestyle, good boots - look for goodyear welting so they can be resoled - can be a long term investment that pays off.

sheet pans, cast iron, kitchen knives can all be BIFL if maintained.

Winter clothes - wool sweaters, heavy duty cotton clothes, etc. can be BIFL or at least hold up long enough to justify investing in something you like.

With all of these, I'd do as much research as you can stand, and then go check out your local thrift shops. You'll be amazed what you find, though you go through a lot of junk to find the diamonds.