What batteries do you have now...
My recommendation is most always the same G-2's or L-16's depending on several things.
WHY
Group 24 MARINE/deep cycle or MARINE/rv.. abot 75 AH each you can use perhaps 25% before damage (Fast aging) Sets in)
Group 27, 29 and 31 just under 100, over 100 and 120-130 respectively.
GC-2 Pairs are DEEP CYCLE Golf Car batteries. you can safely use HALF the power before rapid aging sets in.. and that's 1/2 of 220 Amp hours give or take 10.
The L-16 is nearly tx that (Also used in six volt pairs)
Watts (amp hours time volts) per pound is nearly identical across all lead acid batteries. Flooded wet, Maintenance Free and AGM.
Home was where I park it. but alas the.
2005 Damon Intruder 377 Alas declared a total loss
after a semi "nicked" it. Still have the radios
Kenwood TS-2000, ICOM ID-5100, ID-51A+2, ID-880 REF030C most times