For those interested, you can search through the collections of herbariums all over north America through portals such as the Consortium of Midwest Herbaria[0], in Europe through digHerb [1], and throughout the rest of the world through many other symbiota portals [2].

You can find your nearest brick and mortar herbarium globally through Index Herbariorum[3]. Though these resources are incomplete, they are pretty extensive regardless.

[0]https://midwestherbaria.org/portal/collections/search/index....

[1]https://digiherb.symbiota.org/

[2] https://symbiota.org/symbiota-portals/

[3]https://sweetgum.nybg.org/science/ih/

Also for those in the States, contact your local state University extension office. They know of local resources like this that aren't widely advertised/don't have an online presence.