JOEL, FRANK - Sorry, I have NO idea how the molded rubber seats for the 102, or the 122/123/1X4/1X5 were made. An educated guess would be molded foam rubber then some sort of liquid rubber sprayed onto the foam and then cured.
And Frank, thanks for the new nick-name... I'll add it to my extensive collection.
Wife & I paid a visit to the local Blain's Farm & Fleet yesterday. While I was walkng around the store on my phone talking to SON, I was looking long and hard at this seat,
http://www.farmandfleet.com/products/544084-seat-solutions-universal-fold-down-seat-fits-ztrs.html#
No, not factory, but a real nice seat. And IMO, comfort & durability trumps "original" any day. All three of my CC's could use new seats, or more correctly, My two plus SON's 70.
Eight yrs ago I put one of these seats,
http://www.devonstractorparts.com/product/56+series+cream+vinyl+hyd+will+work+with+mechanical+seat/171
On my #1 snow mover, most comfortable seat I own including my LazyBoy recliner. Wish it would have been on the tractor 45 yrs ago when I was running the tractor 4, to 6, to 8+ hrs a day. It's not as easy to get on/off the tractor as the old pan seat was, but once you're in the seat, you NEVER want to get out. Fold the arm rests down and relax.
The Blain's seat is a scaled down version of the Devon's white Tombstone seat, just right for a garden tractor. I think one of my trctors will get one later this spring, not sure which tractor it will go on though.
Dad took a high back seat similar to the pic's of the WF seat Kraig posted to make one of his CC's easier to get on by swinging his foot/leg over the top of the seat. I grabbed it, the OEM plastic covering of the foam was shot. I bought black Naugahyde, sewed it with Wife's sewing machine to fit the seat pan properly and stuffed some scraps of carpet pad into the seat, put the retaining molding back around the edge of the seat stamping, pulled the Naugahyde snug and trimmed the excess Naugahyde off. Worked fine but was a BIG mistake, normal cloth sewing machine makes too small of stitch, uses too small of thread, effectively cuts the naugahyde where it's sewed. Took about a year for the seam to rip completely across on the 72, but the Naugahyde is still in great shape. Also was the last time Wife's sewing machine worked right, sewing through four layers of naugahyde was more than it was designed for!
The thin plastic coated foam filled seats like my 982 had are cheaper, and do not last. There's no reinforcing fibers or cloth in the covering. It cracks when cold, foam is exposed and deteriorates. For just a little more money, get a seat with reinforced Naugahyde over the foam. With no more than most people run their CC's a Naugahyde covered seat should last 10+ yrs.