The 59mm Mora Edris seems made for this:

https://morakniv.se/en/product/eldris/

qjs

The Gerber Ultralight LST seems made for this too, at 1.96".

https://www.gerbergear.com/Knives/Folding/Ultralight-LST-Knife_46050

My wife had 2 knives and 3 scissors taken from her on a recent trip, so I bought a 6-pack of these for her.

Another inexpensive small knives are Ruike's S collection, blades are 53mm.. so close to the limit, maybe over to the pivot and require modification.

No idea how reliable fenix outfitters (I'm wrong side of the pond) are but seems to have a sale on...

https://www.fenixoutfitters.com/fenix-ruike-knife-s31-stainless/

Knife, scissors, screwdriver/hook/cap lifter tool for $15 so wouldn't get too broken up about it being confiscated.

I appreciate all the suggestions! Though, to be honest, I am averse to buying something new.

Instead I will dig through my bin of old folders and cut one down to a legal size, probably with a non-threatening sheepsfoot shape. I have the gear to do this without ruining the temper. And I'll limit my risk of an involuntary donation to about $5.

It will definitely not be tacticool. But it will have an adequate handle. I'll test drive it during lumberjack and planting season here at the mini-ranch.