Does anybody make...

[Emonortem]

A mandolin with zero - or very low - neck angle and Englemann spruce?

[Michael Lewis]

What are you trying to achieve?

[Clement Barrera-Ng]

.. And are you looking for carved-top or flat top mandolins? Zero (or flat, horizontal) neck angle is pretty common in the latter.

[Emonortem]

You're right, but definitely carved top, with a more traditional, lower arch.

Going for a warm sound and playability for lower action.

[Bill Snyder]

There is not a direct connection of lower neck angle to lower action.

[Beanzy]

Have a look at www.davidsoninstruments.com
I'm saving up for one at the mement. Lovely tone, smooth neck to body transition.
Then saving up again to the bluegrass one from Sim Daley which has a steep neck angle and high-tensioned top.