BTW here are the ratings for the NAPA 7269 8D batteries. The 1340 rating is for 32 degrees, the CCA rating is 1100. (Minor point, but you do want to compare apples to apples).
BCI # : Group 8D
Height : 10"
Battery Length : 20-3/4"
Battery Voltage : 12 Volt
Battery Width : 11"
Battery Cold Cranking Amps @ 0 Degrees F : 1,100
Battery Cranking Amps @ 32 Degrees F : 1,340
Battery Posts Type : Top Post
Battery Reserve Capacity (Minutes) : 325
Battery Weight : 116 lbs
Contents : (1) Battery Assembly
Wet or Dry : Wet
Here is a type 31 battery, that if you put two in parallel, would give you 1400 CCA, and 100 x 2 = 200 Amp Hours. This would require 4 batteries to replace the two 8D's you have.
Each of these batteries weigh 57 lbs, vs 116 for the 8D's. This means that one person could actually move one of the batteries without a crane.
SLI31MDP Xtreme Dual Purpose Battery - BCI Group 31M - Dual Purpose/Hybrid - Marine and Boat - Batteries Plus
Here is a type 24, with 800 CCA, which means with a pair, you would have 1600 CCA. weight of each is 45 lbs, These are meant to be starting batteries, not dual purpose.
SLI24MHP High Power Xtreme Battery - BCI Group 24M - Starting/High Rate - Marine and Boat - Batteries Plus
Here is another type 24 starting battery with 675 CCA (1350 with two) weight is 40 lbs. each.
SLI24MA Premium Xtreme Battery - BCI Group 24M - Starting/High Rate - Marine and Boat - Batteries Plus
BTW I was only looking for batteries with ratings, I do not necessarily recommend these batteries over any others. Only comparing real ratings on batteries.