Average cost of CA cat converter for e30 and install?

[Flash]

How much would a shop generally charge to install? (california magnalow) I know every shop is different but 6 years ago i had to get one installed and someone paid for it and im behind on how expensive things are since im a DIYer but cant weld. Car just failed and i know its the cat as the HC was BARELY below the max and the o2 and plugs/cap, etc are all fresh.
I see different prices for them online and havent looked around town yet but what am i looking at spending roughly?
Any insight is appreciated.

[abrokenframe]

I think somewhere around $300 for the car installed. Can't remember exactly....

Ryan