Just because Dixie Chopper wants use the new Delta 6205 series sealed PTO switch doesn't mean the older Delta 6204 series no longer works. If the OP mower is setup to use the 6204 switches than why spend an arm and leg for the latest and greatest switch. Electrically internally they are the same switch. They just have a different connector and therefore need an adapter harness so it can be plug and play. Still being plugged into an unsealed wiring harness.
The new 679534 is $56.48 vs the old switch from eBay $20 or less (Stens 430-528 - Stens 430-330). Nearly a third of the new switch design.
BTW the same site that previously quoted older PN is now NLA and they are offering no supersede.
But there is a way around things like this by knowing the switch setup. Otherwords there is more than one way to skin a cat. The part doesn't have to be touched by the hands of the Dixie Chopper gods. I actually make more profit (percentage wise) on alternate parts while saving the customer's money at the same time.
It sorta like a customer that needs his Chevy front done. The brake shop is wanting $1300 when the parts only costs $300 plus shipping and that include new calipers, new pads, new rotors, and a few miscellaneous mounting parts as they come as a kit. It should be no than $900 to do the job so going to offer to the job myself. That is with me charging $500 for the parts and around 4 hrs labor. That will include new seals and possibly new bearings.