There aren't a ton of wireless extenders designed for the outdoors, but a few notable manufacturers are Netgear, Ubiquiti ... set your 5GHz band to wireless bridge mode and the 2.4GHz band ...

The U7 Lite packs serious power into a compact form factor. Over the years, Ubiquiti’s ‘Lite’ models have been some of the company’s best bang for your buck in terms of performance.