Yes, stay with the wider tires, you'll be happier I think. The 155s are a bit weak for cornering (I currently have 155s).

The advantage of 155/12 is that they are dirt cheap, with many wreckers practically giving them away (e.g. $10 mounted). They are still being produced massively for cars such as Suzuki Swift (Geo Metro), Chevy Aveo, etc. Sometimes the discount new tire stores sell them $80/four mounted & balanced. Check the Sports section of the newspaper for the occasional tire ad.


But can you still get wide 12" tires? Sure:

165/70 SR12 Yokohama Y372 $42-$43 tirerack.com and SummitRacing.com
165/60 X 12 FALKEN $99.95 MiniMania.com
165/60R12 Falken FK06G $79 TalonTire.com
165/60R12 Yokohama A539 $112 TalonTire.com
165/60 12" Falken $89.95 7ent.com

NOTE: 165-width tires want a 4-1/2" to 6" wide wheel.

Here is a tire height calculations:
Stock tire:
155/80R12 21.8"
165/70R12 21.1 (+ 3% speedometer reading)
205/40R14 20.5
185/50R13 20.3
175/50R13 19.9
165/60R12 19.8 (+ 9%)
165/50R13 19.5
205/40R13 19.5
165/55R12 19.1 (+12%)
http://www.discountpartcenter.com/tirecalc.html

So that's the disadvantage of low-profile tires: your speedometer will read too fast and the effective gearing will increase, making it rev even higher on the freeway ...

What about tires for 13" or larger wheels? See these discussions:
Shopping for 13" tires
How to fit 17 inch wheels
tire size sugestion and question