Lumbar back support - advice

My A4 Audi cab isnt a sport & therefore does not have electric seats with lumbar support. Ive read a retrofit is too expensive/too hard so im looking into other forms of lumbar support

Anyone with experience offer suggestions on the best combo of perhaps looks/comfort for buying something which aids in lumbar support?

i would really appreciate it as there are loads of "cushions/meshes" on the internet.. & i havent a clue how good they are

Cheers