"Ultimately", it is always possible to have custom made Ohlins for our R3 by the Ohlins French importer (PFP-Racing Ohlins France).
PFP is used to do it for cafe racer motorcycles and cars including for racing. Their reputation is excellent.
It is a small company (14 employees) created in 1983 but who delivers thousands of rear shock absorbers and hundreds forks each year !
Their catalog includes 19,000 references (!) but they still explain on their site that if we don't find a reference for our motorcycle, we'd just need to contact them as they've been used to custom made since 1983 !
"Parmi nos 19000 références, si vous ne trouvez pas de produit adapté à votre moto ou à votre usage, contactez-nous car nous réalisons des produits ÖHLINS sur-mesure depuis 1983... "
They've developed rear shock absorbers for the previous Rocket model and recently for the Triumph Bobber (as well as the fork).
Moto - Produits