Let $\mathrm{Bundle}$ be the category whose objects are smooth vector fiber bundles over $\mathbb{R}$, and morphisms are fiberwise smooth linear map (that is, the base is not assumed to be fixed).
Let $Base \colon \mathrm{Bundle} \to \mathrm{Diff}$ be the functor returning the base of a given bundle (and the morphism between bases of a given bundle morphism, respectively). Let's define $ \mathrm{FunctorialBundle}$ as the full subcategory of $ \mathrm{Func}(\mathrm{Diff}, \mathrm {Bundle})$ on those functors that are section to $Base$ (that is, $ F \in \mathrm{Ob}~\mathrm{FunctorialBundle} \ \Leftarrow:\Rightarrow\ F \circ Base = id $).
Question 1: Classify objects of $ \mathrm{FunctorialBundle} $ up to isomorphism.
Of course, my question is rather "is such a classification possible?". Or is the class of such functors immense and the classification problem does not make sense (just as the problem of classifying all finite magmas, semigroups, groups does not make sense)? My next question is an example of an answer:
Starting with tangent bundle $TM$ and one-dimensional trivial bundle $\mathbb{R} \times M$ and applying operations direct sum, tensor product, dual we obtain all tensor bundle functors (whose sections are tensor fields). If there are some standard operations that extend the functor class, then add them to this list.
Question 2: are there functorial vector bundles (that is, objects of $ \mathrm{FunctorialBundle} $ ) that are not in this class (up to isomorphism, of course)?