Need to rebuilt under carrage cann't find anywhere to buy parts. Anybody have a suggesting
You will have to find used in reasonable shape or do without papatim, 7" pitch is no way, no how available from anyone today. My HD7G has the same rails, I got lucky and found a set off a donor tractor for mine. With segmented rear sprockets and the availability to 6.906 CAT rails many of the Aussies have upgraded to Cat undercarriage, rollers and all. None of the old suppliers will even consider running the lines today for less than 50 full sets then you still need rollers, segments and idlers work. Good luck.
One potential, if segments are worn but not too far gone, and you can have the rollers reworked in a machine shop to fit rail dimensions, could install 50% worn 6.906 Cat rails directly to your machine, at 50%+/- wear they are right at 7.0, if sealed/lubricated could last a long time.
Thanks I will check around with shops
Did a little more digging on your machine, the spec is not 7.0 pitch but 6.93(27.72" measured across four links), the 6.906 should work actually better when new/newer but there is probably going to be height difference to links, not certain how that will affect it. May want to see if a Cat or HE dealer that does undercarriage has a section of old 953/955K rail you can examine and compare with.