Good morning afternoon. So I've just finished stripping down my DT 400 for painting. And after a colossal struggle to get the swing arm bolt free, the bolt is no longer recoverable. 

My question is there an aftermarket pivot/ bolt available somewhere in the internet, I tried partzilla and they don't have any available. Ebay has some but the cost of postage from the US to Australia is many times the value of the part ($120ish) .

Any help would be appreciated, having been the first dt I've worked on I will for now have more questions then answers to contribute. 

Kind regards, Alby.

A good hardware store should have one or be able to order one.  You just need to measure the diameter and length.  Grade 8.8 minimum.
 

Thanks mate. I appreciate it. I can get the shank measurement, but unfortunately the total length is unattached as I had to drill the bolt out to free the swing arm and then put it in a press. I believe from memory there was a step from shank to thread
 

Same part number was used from 1970 to 1976 for the 250/360/400 so that opens up a lot more possible models to look for. 

Very "axle bolt" like so possible if say front or rear axle is same OD and possibly a bit longer you could have any machine shop cut it down and thread it.   A machine shop could probably make you one from scratch as well. 

P.S.  Shouldn't be too hard to get the length by measuring across frame brackets or even the swingarm itself.

Thanks alot, I will get the measuring tape out. Gives me some options 

Welcome from NZ. Be sure to grease the arm bolt well so it carries grease through the spacer without wiping it off. There's a grease nipple on the arm itself--or should be-- but that only gets the grease to the moving parts, bushes etc, but that doesn't get it to where it seizes solid through the middle. It's the Bane of the farm bike world where i spent most of my working life with seized up arm bolts. There a pic up here on the site somewhere from long ago with a steel tube & steel foot with bike lying on its side resting on the tube over the bolt head then might show a fat Honda crank pin with long handle which I probably got my wife to hold & atacked it with a steel sledge hammer. Not many bolts argue with that haha.

Thanks for the heads up, I will grease it up properly once I sort out a replacement pivot. Not sure what this bike was before me could have been a farm bike, lots of sand everywhere so maybe ridden on beaches , and salt would not of helped. It passed through a few hands before me and went into the to hard basket. 

I will have to find that picture! I had a heavy persuader didn't do anything really I had maybe two mm play after a lot of persuasion. Had to cut the it in the end a bring it to work an use a hydraulic press, pretty much welded to the sleeve by rust. 

I believe the part number is 275-22141-00
remarcables.com.au are saying they have two in stock, but not giving a price on their website.
Here's the model listing to help you search.

DT1E 1971 USADT1MX 1971 USADT250 1974 USADT250 1975 USADT250 1976 USADT2MX 1972 USADT360 1974 USADT400 1975 USADT400 1976 USAMX250 1974 USAMX250 MX360 1974 USAMX360 1973 USAMX360 1974 USART1 1970 USART1B 1971 USART1M 1970 USART1MX 1971 USART2MXP 1972 USASC500 1973 USASC500 1974 USA

Thanks Pete I will have a look now. I appreciate your time mate.  
And thanks for the resource, I hadn't come across these guys before.

Found my pic of how i do it. Waterpipe welded to a steel plate. Honda crankpin & a bloody big steel sledge hammer. Rarely fails to move it.

photos.app.goo.gl/3wePMukEnMWhUWWg6