1962 Other Jaguar Models Front side-to-side ride height unev

Jag Mk 2 3.8 workshop manual recommends using spring spacers positioned on top of a spring to offset the effect of uneven length front springs. I have tried to locate spacers but suppliers say "no longer availalble". Do you know a source for correct type spacers, new or used?
I have seen this problem addressed with spacer washers installed on the retaining bolts of the the lower spring support, but feel that this puts unacceptable stress on the bolts due to the reduced length of the bolt thread used. The rear suspension has been rebuilt with all new parts and I am sure the ride height problem is in the front suspension.