Forestfarm (very good G.WD. rating) has relatively larger Platanus wrightii specimens. Cactusstore.com (very good G.WD. rating) has Vauquelinia californica seeds. A number of wholesale sources offer Platanus wrightii, Vauquelinia californica, and Vauquelinia corymbosa...so you might want to check with a local nursery to see if they could help.

thanks for the info.. already knew about forestfarms plants---too big (5 gal.)for reasonable shipping costs for my budget at least. most of the local nurseries don't do special orders of that nature as they don't do business with those whole sale sources who are mainly in southern California and Arizona. checked cactusstore for the sycamore (which they didn't have) but did not think to check them for the vauquelinia (which they apparently do, LOL). thanks again. really appreciate your help.