I wouldn't be sure about that brake booster. They can fail spectacularly, feeding a pile of brake fluid into your intake and leaving you with a huge cloud of smoke / clogged exhaust valves and ports and no brakes.
Get it fixed ASAP.
Get it fixed ASAP.
Now, could a master cylinder and a brake booster fail this way? I suppose if the brake booster was already failed and leaked vacuum at the booster/cylinder interface, and then the master cylinder seal at the main plunger also failed, that this could happen. But I don't see one causing the other.
Since then, any sign of a leak == park it and take the bus.
Other than that, the first spider I had was a wonderful thing. Plenty of performance, dynamic handling, looked gorgeous. The 2nd one was a complete sh*tbox because it was allowed to rust and never fixed properly or drove properly.
Chryslers have a bad reputation in Australia. Poor quality control, bad reliability (compared to Toyota), hard to get parts, interiors that eat themselves etc. I should know having owned a few (and rebuilding a 300C at the moment). Once they bought AMC all the terrible Chrysler problems seemed to be like a virus on Jeeps.