For both. You pay shipping.
Differential came off my 1800. Has a little over 70K miles on it. Still rins great, no damages to it.
Swingarm off a 1300 with approx. 35K miles (according to the seller I bought the set from).

I changed out the differntial on the VTX 1800R of mine to a 1300. It has worked out great! Still have more than enough low end, but the upper end cruises a lot better with slightly better mileage, and the speedo is spot-on correct now.