I definitely get a beachy, suntan lotion vibe from Tommy Bahama Set Sail St. Barts for Men (I think it can be a unisex fragrance). I was able to find it on discount ($19.99 for 100ml bottle) at TJ Maxx in the US. Maybe TK Maxx would carry it in the UK.
In the same vain, there is also Creed Virgin Island Water - marketed as a unisex fragrance. But you will pay a bit more for that.
Sephora's in the US carry some Demeter fragrances.
Good luck on your search.