Anyone know where you can buy some that go close?

All the ones I see on Ebay or from places like Kingswood Country are 200mm or more long meaning you have to cut them and then blast off the powdercoat and then repaint them. Plus they are 12mm bar which I don't think will fit through the bottom plates.

I have some HZ cab-chassis ones that will work, they are for 3" axle tube, 162mm long from top of curve to end of thread and probably 3/8" bar and thread. However they are a bit knocked around in the threads plus the nuts are a bit rough too.

These are for my HK GTS, using a 9" with HQ-WB commercial perches and bottom plates. By measurement I could do with 10mm shorter than the tonner ones but would still work. Tubes are 75mm, tube top to saddle base is 90-95mm, springs are 30mm and bottom plates are 5mm which is 125-130mm from the inside of the curve to the where the thread pokes out the bottom plate. These tonner ones are 148-150mm from the inside of the curve to the end of the thread.

Try asking a place that does spring retempering (or whatever it is called).
They usually sell u-bolts as well. These may be too long but they might be willing to do a set of custom ones.
I was going to do this but the bloke behind the counter in an Adelaide shop didn't give me the impression of giving a crap about doing a good job, so I reused to old ones with new nuts.

The nuts will be available from a specialist nut, bolt and fastener store. Take an original nut in and ask if they have any. That worked for me. There is generally at least one specialist store in every capital city.

I can relate. Sometimes it is just easier to get someone else to do it!