Hi Irit.
To substitute the pear purée in your vanilla butter toffee recipe, you can use cream in the same quantity, though this will affect the flavor profile and texture. The pear purée adds acidity and natural sweetness, as well as a bit of smoothness to the mix. Using cream instead will result in a creamier caramel with a slightly less fruity taste.
For fruit caramels, yes, you can use other fruit purées instead of tropical ones. Just keep in mind that each fruit has its own acidity level and water content, which can alter the final texture of the caramel. If you use more acidic purées, like raspberry or strawberry, the caramel may have a tangier taste, while sweeter purées, like apple or mango, will give a milder flavor.
Greetings.