https://www.rehabvintage.net/

https://industrialartifacts.net/

Some nice vintage furniture and miscellaneous hardware.

https://www.ebay.com/itm/155257403398

An Underwood & Underwood cabinet for storing stereoview (or stereograph) photos. Could potentially repurposed as a zettelkasten cabinet as the slip sizes should generally be compatible.

https://www.joann.com/harry-potter-cotton-fabric--quidditch/16028581.html

Bought a yard of this yesterday to reupholster two Steelcase chairs. It's just enough to cover them both.

https://www.worthpoint.com/

https://americanhistory.si.edu/collections/search/object/SILNMAHTL_34484

https://www.newmarkettoday.ca/remember-this/in-its-heyday-office-specialty-employed-400-in-massive-complex-18-photos-1851941

reply on: https://www.reddit.com/r/antinet/comments/wzblc9/card_storage/

The smaller 1 to 3 drawer vintage metal card files are readily available on eBay usually between $15 and $40. This isn't bad given how expensive new files can run. Many were made with small fittings that allow them to be stackable. Usually these are sturdy, but light enough for relatively inexpensive shipping.

The larger multi drawer full cabinets can run a couple hundred, but their bigger issue is that they're so large and heavy that they can be in the range of $800 or more to ship anywhere. If you want something like this, your best bet is to try to find something local that you can drive to and pick up locally. If you're into 4x6" cards, double check with the seller to make sure that they'll fit. Often even the somewhat larger cabinets are a 1/4" too short for 4x6 cards, much less the slightly taller tabbed cards (A-Z) you might use for separating sections. I've refinished some old steel furniture like this in the past and it's not easy or cheap, but if someone is desperate...

https://www.ebay.com/b/Index-Card-File-Cabinet-In-Office-Filing-Cabinets/3299/bn_7022123911

Those who might want something new might also look into Bisley which makes some reasonably nice card index files with and without locks, though you might have to order them directly through their New York Offices. https://www.bisley.sk/userfiles/bisley/product/e84b22bf2d7156d048ad076ff74f895d.pdf

https://www.washingtonpost.com/archive/business/1990/08/06/after-20-years-singer-furniture-leaves-parents-to-go-solo/5fea73cb-bb3f-436d-b2a2-0e70a6824e47/

https://www.1stdibs.com/blogs/the-study/dimoremilano-capostipite-shelving-system/

https://www.officebarn.biz/shop/used-office-furniture/used-file-cabinets/used-specialty-file-cabinets/9-drawer-card-catalog-file-by-remington-rand/

9 drawer card catalog file<br /> Remington Rand

https://www.officebarn.biz/shop/used-office-furniture/used-file-cabinets/used-specialty-file-cabinets/8-drawer-card-catalog-file-by-allsteel/

8 drawer card catalog file<br /> Allsteel

https://nextdoor.com/for_sale_and_free/aa66e37b-7875-4868-8e5f-22b34b84d9ec

4 drawer metal filing cabinet $25 from Amado Ulloa in North Pasadena Heights In good condition Included keys as well

Not quite 20 gauge vintage, but reasonably nice.

https://losangeles.craigslist.org/sfv/for/d/burbank-stackable-card-file-cabinet/7414409456.html

Steelmaster file card cabinet

https://www.etsy.com/listing/516040483/vintage-industrial-steelcase-index-card