Welcome!
Akrumm,
First - welcome to the TDR. As you will find, there is a wealth of information here.
Do a search on "seats" or "cushion". You might find what you are looking for. There is another post currently running about adding foam to the seat bottom - maybe that would help.
Also may want to repost your question under the 2nd Generation Forum for better exposure (or the moderator may move it for you - hint!) Takes a while to get used to all the features of the site - good luck in your search.