A single angle, single phone model windshield mount -- a job for a 3D printer?
You'd need to print in a heat resistant material - ASA for example - and design the part for your needs, but this project is certainly feasible and doable with 3D printing. If that isn't enough for you, you could drill a hole to the internal cavity (it's best to have an infill pattern that does not split the internal cavity into several ones. Gyroid is one of these) and fill it with resin to make it even more sturdy.

With the right design, you could also go for SLA/DLP aks resin printing, but I am not well versed in the properties of printed resins but that they have some of the best inter-layer bonds.

If you don't want to get a 3D printer yourself, order the part printed, which usually comes cheaper than an entry-level printer with better quality for a one-off project as you won't have to learn the ins and outs of your printer and how to ensure the quality in the material you choose. Some print services also provide really exotic materials.