Help with finding replacement wheel for old bike
Hi, I recently picked up a bike that a bike shop near me was throwing out for free and I want to get it fixed up for my girlfriend as a gift (cause shes the one who grabbed this specific one from the shop). Now the rear wheel is completely bent severely and no chance of me bending it back into shape. I though it would be easy to find a replacement but I quickly learned that I know nothing of bikes in general.
I learned that the bike is a 1987 Murray Road Bike and the numbers on the bike wheel I took off are 37-590 (26 x 1 3/8) unfortunately when i type that in anywhere I just get the tire (the tube?) and not the metal rim part. Also as well, i only ever see the front wheel being sold never a back wheel. I guess heres my question, since i literally know nothing about all these sizes and stuff, can anyone recommend a site/link to a site that sells what I am looking for? or at the very least let me know what i should be typing in to find this replacement?
Sorry if i didnt give enough information about it, i really do have no idea about bikes other than how they work so i dont know what is needed or not.