G'day all!

I have a 1990 TD42 Wagon, with just about 300k on the clock. I recently had a guy look over the electrics for overall health, and I asked him to check the output of my alternator.

He was adamant me it has just about had it (the alternator), and suggested at $600 to have a new one fitted. If I was to buy a new one, is it worth sticking to the orginal 70aH or upgrade to a 90/120 while in the middle of the it all? Am aware of the need of the vaccuum seal, right mounts etc.

I use the car for just a Engel fridge full time, the odd phone charge and lighting at night.

Hope someone can shed some light on this! Appreciate it fellas =)