How do, 156 air boxes in totally good shape are a rare thing but a call to the breakers that list bits on flea bay will sort you out with one. An alternative way to go is to keep the existing botched air box, stick a length of silicon tubing on the MAF sensor housing, down to the filter box, then put a big aftermarket filter on the end of the silicon pipe in the box. The filter box size and location on 156s is actually really rather good.
If it were my money, I'd try to find a good second hand one.
On the AC condensor, flea bay lists one for your car brand new at £69 at the moment. Fitting is a DIY job, then off to get it gassed up.