Hi Moti, I used to take the Miata to the track and it has a rollbar - used to autocross it as well - but about 5 years ago got a Birkin S3 (That's like a Caterham 7 with a south african chassis - hence the handle) for this purpose.
In the last couple of years I started doing more off-road rallycrossing with my wife's Subaru. We have 2 kids now - so not enough time to do both on and off road events - so when I have the time - I mostly do the rallying with the grocery getter.
When the kids will get older - I plan on getting an old Subaru, put a rollcage in it and go for club rally events. In the meantime - just rallycross for me, I am afraid.
Here is a picture of the Birkin - it looks a bit different now - have a Kirkey racing seat in there and it is not as shiny. I now need to decide if I want to invest more money in it - remove the windscreen and replace with a brookline screen and wink mirror - or sell it and experience something else.