Seems like a community of deep research people. Who bought their kids a swing set and like it? Bonus if it survived multiple winters.
@RebeccaSlatkin we have got a swing+climbing set made from massive larch wood. Sanded, but otherwise untreated. The swings are similar to ones at playgrounds: they hang on chains, seats are rubberised plastic with metal underside. Originally built when out son was 3, survived 10 Central European winters thus far with minimal maintenance.
@_nd_ oh my lord! FedEx it across the pond when you’re done?
@RebeccaSlatkin freight costs might make that quite expensive. The whole set cost about 500€ back then, without assembly. Maybe you could find a contractor that builds something similar. Around here there small businesses that build such a thing are rather common.
The seats are very similar to the flat seats at https://www.outdoorplayuk.co.uk/swing-seats/ and larch wood has the image to be durable and with little (not none) splinters.
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@RebeccaSlatkin it you need images for a potential contractor to convey what to build, maybe this helps: https://www.silberholz.at/kategorien/spielgeraete/spielkombinationen (German only, but I think they get the gist).
Spielkombinationen

Endlose Gestaltungsmöglichkeiten mit unseren Spielkombinationen

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@RebeccaSlatkin Paid too much for a wood set from The Swing Set Co whose swing sets seem to have outlasted their online business (their website seems to no longer work) 😅

Pretty happy with it, though. Maybe something used from Facebook Marketplace or eBay would be a good value…

@RebeccaSlatkin We bought a swing kingdom 11 years ago. The swings and swing set itself are still in great condition, but the canvas tops took a beating (we have no trees in our backyard and lots of wind). Replacement canvas tops are expensive, so I havent bothered to replace them. I think they have plastic tops now, which I would go for if doing it again.
@RebeccaSlatkin we got one on craigslist. Had it up maybe ten years? Craigslisted to another family. SoCal.