My Mac had to have major surgery so I lost al my apps and a new Ventura operating systme was added.
Now...CS 5 and 5.5 cant be installed for obvious reasons.
Is there any way I can continue to use CS 5.5 without major expense as it is not something I use often but when I do need it it is intensive.
no chance, I think. You need an old machine where you can install MacOS 10.6.8 or perhaps MacOS 10.10 to run InDesign CS5 or CS5.5 successfully. I wonder what operating system was in place before the machine broke. Is it still the same machine?
Alternatively you could subscribe to InDesign for Creative Cloud on a monthly basis.
And quit subscription after a month.
( Adobe Community Expert )
Perhaps by installing an older OS as a virtual machine?
Short answer: no.
Longer answer, when you need it, subscribe to InDesign only on a month-to-month basis. You'll have the most updated and compatible version and you'll only have to pay for it when you use it.