My mother (who ran a biochemistry lab) had a longish one--extra digit of precision I guess. Unfortunately my anti-packrat dad must have chucked it in some move or another. In addition to some cheap student stuff, I think I still have a couple of "normal" professional slide rules but they're not in very good shape if serviceable.

Faber-Castell had new-old stock in the mid 20-teens, but they ran out (of stock or patience) around 2016–2018. Picked up a 2/83N for under $100, and I wish I'd gotten more. I'd suggest some of those are on eBay now.

Most of my like-new rules came from antique malls, though I've also purchased one from Etsy. Estate sales are occasionally fruitful. As long as they were stored properly (e.g., in a desk drawer, like it seems they mostly were after the electronic calculator took over), they don't degrade. Occasionally you see minor yellowing that is cured by some time in the sun. Carrying cases (often leather) are typically more affected by time. I soak new (to me) leather cases in neatsfoot oil and give them at least a week before putting the rule back.

You could make your own with prints from the Slide Rule Museum [0]. 3D printing would make quick work of it, but I'm sure wood or metal units could be accomplished. The cursor benefits from spring loading,

They also have some pretty nice simulators [1], if that's your thing.

[0] https://sliderulemuseum.com/SR_Scales.shtml [1] https://www.sliderulemuseum.com/VirtualSR.shtml

The used ones aren't that expensive on eBay, especially if you just want a functional one and not a pristine show piece. There's a few 3D print models available for them too, and honestly they are rudimentary technology, you could probably make one with hand tools and patience.

I bought a newly manufactured one from ThinkGeek several years ago, some geek-catering company will pop up and supply pent up demand eventually. Curiosity Box fills that niche right now.

As per sibling comment: not much of a market for new ones. Would be curious about someone trying to make some: use Kickstarter to gauge interest perhaps?

For used, see perhaps "Where to Buy Slide Rules?":

* https://www.sliderule.ca/buy.htm

They won't be new, but Ebay has a lot of old linear rules.