My Phil Jones rig is full of 5” speakers, so an 8” will be fine for your purposes, just pick something you like the look of really. The Ampeg at least has some aesthetic thought gone into it.
Just remembered the Soloking Roscoe Beck type basses. Anderton's have stock of blue and black https://www.andertons.co.uk/soloking-mj1-classic-4-string-bass-in-lake-placid-blue/ https://www.andertons.co.uk/soloking-mj1-classic-4-string-bass-in-metallic-black/ and here's a link to the thread about them