New BMW center stand is $350 plus the small parts. I have an 81 R100RT with a Reynolds ride off stand it will also fit the 82 R100RT as long as it isnt fitted with the Nivomat shocks.
You need stand #328 that is made for the bike. I have two small pieces of 2X4 that I use to elevate the bike when changing tires. I love the ride off especially when fully packed for tour camping.
The number is stamped at the top flat area on the down legs.