Thinking of a latex mattress — should I use high-density foam or rebonded foam as the base? (20M, 80 kg, want cooling layer)

Hi— I’m shopping for a new mattress and could use advice. Quick details: I’m a 20-year-old male, ~80 kg, usually sleep on my side + back. I’m planning to buy a latex mattress (prefer natural or blended latex). I’m unsure about the base layer: Option A: a high-density foam base (HR/HD foam) with latex — seems durable and firm. Option B: a rebonded foam base (recycled bonded foam) with latex — I’ve read it’s very firm and supportive. I also want to add a cooling gel/foam layer on top to keep the surface cooler — aiming to lower feel-temp by ~3–5°C if possible. My main goals: good spinal support for my weight, long life, and cooler sleep (I sleep hot). Budget is midrange; open to brands/DIY toppers. Idk whether to buy from branded companies or get a matress made from a local company