Spare tire wheel well on 1964 Plymouth Barracuda...what size 14 inch tire fits?

Thanks so much for your offer...have several of the 14 x 4.5 rims to choose from...just refinishing the rallye wheels now to get them ready for new rubber. Cuda 340, mine is the original carpeting with the thick backing .....I agree it might be unlikely that it lays completely flat with the 185 tire....the biggest thing is to ensure it fits as there is really no room to haul it around inside the trunk proper....thanks again. Greg