There are two main rust diseases of pears in Oregon, Pacific Coast Pear Rust (Gymnosporangium ibocedri) and Trellis Pear Rust (G. sabinae). Rust fungi typically have two different hosts, the primary host (e.g. your pear tree) that will display severe symptoms and a secondary host (e.g. your neighbor’s incense cedar or juniper) which may only display minor symptoms and effects. Distinguishing between the two species of rust requires careful examination. From the photos, it appears that you are dealing with Trellis Rust, which causes acorn shaped aecia on the lower leaf surfaces later in the season (for a comparison of the two, refer to: https://blogs.oregonstate.edu/mgmetro/2018/06/01/pear-trees-rust-times-2/)

Pear rust can affect both European and Asian varieties of pear. There are no listed resistant varieties for Trellis Rust. There are no chemicals registered for home use for either species of rust, so you would need to hire a company that is licensed to apply a commercial pesticide (see: http://npic.orst.edu/pest/selectpco.html). Other management practices include collecting and discarding infected leaves and fruit, remove and destroy any infected woody plant parts, and of course removing alternate hosts (junipers) from a 1,000 ft radius, which isn't feasible if the host is in a neighbor’s yard. For more on Trellis rust, refer to: https://pnwhandbooks.org/plantdisease/host-disease/pear-pyrus-spp-trellis-rust-european-pear-rust