Needing a battery for my '73 bog block

[Yellowshark]

Hi wondering wha you guys are using. I currently have a Varta E38 blue 75ah and cca of 720a. I am looking at a Varta E44 Silver 77ah cca of 780a. So fine for my 5a charger and sufficient cca for the big block; I did have 800+ cca many years ago but the E38 blue with only 720a was fine. Oh supplier is Tanya who I have used for many years now

Cheers,
Pete