it probably has a leather seal. you will want to count the spring coils. measure the wire diameter and also the inside diamter and length of the spring.
although the spring will probably not be the originla length due to sag from age.
you may be able to find a spring that will work by checking Jim Maccaris website for his springs and buying something that will fit.
finding a leather seal will be difficult but you may be able to make one or the existing one may be able to be rejuvinated. what i would suggest is going to this site and seeing if someone can help
http://www.network54.com/Forum/405945/