If anybody finds you need a battery for a gen1s , NAPA has the group 47 r53/r52s battery on sale for $107.10 from 153.20.....
It is an exact fit battery with the vent tube connections, and is 660 CCA battery, 18 month warrenty...not the best, but since most batteries are now $180+, it might be "good enough" for many folks....I know its not the best, biggest, lightest or most powerful, but sometimes a good deal is good enough depending on how long you will own the car.....
I am using it yo replace an 6 year old optima redtop battery that seems to have a dead cell that drops to 10.5 volts in 24 hrs (yes..tested)...but still cranks the car fine..lots of cranking amps left, started the car at 5° f.... Go figure, but was time.

 

Thanks for the tip, Zippy! I'm going to pick one up in Bedford NH tonight. My car has been cranking a little slow on our colder mornings lately and I get the occasional center instrument cluster buzz indicating low voltage too. Just looked and I'm only on my second battery (last replaced 02/2008) so I think it's time to play it safe and replace - an even easier decision with a good deal like this!